# A lesson in attention to detail

Background (to be read): In 2023, I created and posted on this site a series of puzzles called A Trivial Pursuit. This involved creating 24 themed puzzles, each of which produced a one-word final answer, which - once all 24 answers were combined together in a particular way - would help to solve a final meta-puzzle.

There was one puzzle which I created for the series that I had to drop and entirely redesign at the eleventh hour, as a final double-check revealed a fatal flaw that had been present in its construction from the very beginning and which would entirely break the meta-puzzle. However, by itself it's still an interesting type of puzzle (I believe, anyway) worth posting, and sharing it here might serve as a reminder to all (me included!) of the importance of double-checking your puzzles before you hit 'Post'...

The puzzle now follows, below.

You hold in your hands 12 paper scraps from a shredded sheet of sequential instructions. It's clear that the section from the very top of the page reads:

• Delete all letters also present in her 11-letter pen name.

...and the one at the very end reads:

• Apply the instruction you see before you to the original string.

However, the main body of the instruction sheet has been sliced into a number of different sections - each featuring exactly two instructions - that seem pretty much impossible to reassemble into the correct order by eye alone... You're going to have to reconstruct the original instruction sheet by other means...

TASK: (i) Use the 10 jumbled sections below (along with those above) to reconstruct the original instruction sheet in full, (ii) Give the final one-word answer to this puzzle, and (iii) Explain how this was problematic for the original puzzle series! (You may find it useful to refer to the meta-puzzle itself...)

• Delete the second occurrence of the only 2-letter sequence that appears twice in the string.

• Replace the last vowel with the name of the fourth-largest moon in the Solar System.

• Insert an 'R' to form the name of a Frankish count who conspired against Charlemagne.

• Change one letter to form a 5-letter fruit; remove it from the string.

• Insert an 'S' to form a 5-letter word meaning 'goodbye' in a European language; remove it from the string.

• Insert a letter immediately before the last letter to form the name of the 16th letter of the Greek alphabet.

• Insert the word 'ME' immediately to the right of the first instance of the letter 'I'.

• Remove the first letter to contain a curved section and the last letter to comprise only straight lines.

• Replace the name of a country with that of a neighbouring country also known to have nuclear weapons.*

• Insert the 2-letter code of the smallest US state (by area) between the two identical letters that neighbour each other.

• Replace the surname of a UK PM with that of her immediate predecessor.

• Replace the name of a Biblical figure in the book of Genesis with that of his father.

• Reverse the entire string.

• Replace the name of an American rock group with the surname of its lead singer.

• Reverse the letters in the first half of the string, then move the result to the end of the line.

• Remove each instance of the first chemical symbol in the Periodic Table.

• Swap two adjacent letters to form a 6-letter synonym of 'modify'.

• Replace a 4-letter 1995 single with the 9-letter name of the band who performed it.

• Swap two adjacent letters to form the name of a performer with a hit song called 'Holiday'.

• Replace the two central letters with a single 'O'.

* NB At initial posting the clue marked with an asterisk erroneously contained the word 'also'. This - ironically, given the question title and context! - was an unintended error that affected the interpretation of the instruction, and has now been rectified in an edit removing it. No harm has been done to any answers posted before the change, but my apologies for any inconvenience to solvers whose unposted attempted solutions were affected by this typo. The lesson at the heart of this question still stands - doubly so!

• I didn't solve this because (it seems to me) the question is flatly wrong. It refers to rot13(n pbhagel naq "n arvtuobhevat pbhagel nyfb xabja gb unir ahpyrne jrncbaf") but unless I am confused and/or misinformed rot13(gur pbhagel va dhrfgvba vf abg xabja gb unir ahpyrne jrncbaf). Apr 5 at 19:16
• I know that I would have solved (several hours ago) without this because having (as I thought) figured enough out by hand-experimentation to know which songs, countries, etc., were which, I wrote a little program to try 'em out and report on anything that successfully applied all 10 operations in some order, and when it failed to find anything after I'd fixed all the bugs I could find I assumed I'd made some stupid error somewhere (and then had to go and do something else) -- but on running it again [... continues] Apr 5 at 19:19
• [continued ...] with the "correct incorrect" information in it, it rapidly finds the correct answer. Apr 5 at 19:19
• @GarethMcCaughan Ah, I'm very sorry - the word 'also' was erroneously included there. Ironically, this puzzle has lived up to its title in a second way! Thanks for pointing this out and apologies for the time you might have wasted with that endless rabbithole.
– Stiv
Apr 5 at 19:24

Okay let's go through this step by step.

(I'll illustrate the changes in each step with plain but hopefully intuitive ASCII notation. Small letters are to be removed. The words used in the modifications are just annotated in the original instructions for easy reading (and lazy typing). Sorry, people, no links today. I don't have to explain you about Frankish conspirators or 1995 hit singles, do I?)

(0)

Start with the string 'WRITERMARYANNEVANS'. Delete all letters also present in her 11-letter pen name (George Eliot).

W(RITER)MA(R)YANN(E)VANS
WMAYANNVANS

(1)

Replace the surname of a UK PM (Theresa May) with that of her immediate predecessor (David Cameron). Replace the name of a Biblical figure (Onan) in the book of Genesis with that of his father (Judah).

W(may>CAMERON)ANNVANS
WCAMER(onan>JUDAH)NVANS
WCAMERJUDAHNVANS

(2)

Reverse the entire string. Replace the name of an American rock group (R.E.M.) with the surname (Michael Stipe) of its lead singer.

(WCAMERJONAHNVANS)<
SNAVNHADUJ(rem>STIPE)ACW
SNAVNHADUJSTIPEACW

(3)

Swap two adjacent letters to form a 6-letter synonym of 'modify' ('adjust'). Replace a 4-letter 1995 single (Just) with the 9-letter name of the band who performed it (Radiohead).

SNAVNH(AD(U<>J)ST)IPEACW
SNAVNHAD(just>RADIOHEAD)IPEACW
SNAVNHADRADIOHEADIPEACW

(4)

Insert an 'R' to form the name of a Frankish count who conspired against Charlemagne (Hardrad). Change one letter to form a 5-letter fruit (Peach); remove it from the string.

SNAVN(HA(R)DRAD)IOHEADIPEACW
SNAVNHARDRADIOHEADI(PEAC(w>H))
SNAVNHARDRADIOHEADI

(5)

Insert an 'S' to form a 5-letter word meaning 'goodbye' in a European language (¡Adios!); remove it from the string. Insert a letter immediately before the last letter to form the name of the 16th letter of the Greek alphabet (Pi).

SNAVNHARDR(ADIO(S))HEADI
SNAVNHARDRHEAD((P)I)
SNAVNHARDRHEADPI

(6)

Reverse the letters in the first half of the string, then move the result to the end of the line. Remove each instance of the first chemical symbol (H for hydrogen) in the Periodic Table.

(SNAVNHAR)< <-> DRHEADPI
DR(h)EADPIRA(h)NVANS
DREADPIRANVANS

(7)

Replace the name of a country (Iran) with that of a neighbouring country known to have nuclear weapons (Pakistan). Insert the 2-letter code of the smallest US state (by area) (RI for Rhode Island) between the two identical letters that neighbour each other.

DREADP(iran>PAKISTAN)VANS
DREADP(RI)PAKISTANVANS
DREADPRIPAKISTANVANS

(8)

Swap two adjacent letters to form the name of a performer with a hit song called 'Holiday' (KSI). Replace the two central letters with a single 'O'.

DREADPRIPAK(I<>S)TANVANS
DREADPRIP(ak>O)SITANVANS
DREADPRIPOSITANVANS

(9)

Delete the second occurrence of the only 2-letter sequence that appears twice in the string (AN). Replace the last vowel with the name of the fourth-largest moon in the Solar System (Io).

DREADPRIPOSITANV(an)S
DREADPRIPOSIT(a>IO)NVS
DREADPRIPOSITIONVS

(10)

Insert the word 'ME' immediately to the right of the first instance of the letter 'I'. Remove the first letter to contain a curved section and the last letter to comprise only straight lines.

DREADPRI(ME)POSITIONVS
(d)READPRIMEPOSITION(v)S
READPRIMEPOSITIONS

(11)

Apply the instruction you see ("Read prime positions") before you to the original string.

WRITERMARYANNEVANS
_RI_E_M___A_N___N_

Phew! We have an answer. Why coiuldn't it be used in the puzzle?

The meta answer concatenates all answers, but takes only every other letter. The actual answer used is REIMANN, the name of an American architect. RIEMANN, an arguably better known German mathematician, would have turned Brian Eno into Brean Eno.

It's hard to find alternatives for the pattern R.I.A.N. Onelook's only useful alternative is "Roiyaan", the title of a single by a Pakistani artist. (That might not have been a terrible choice, because apparently the Urdu title means "I cried!")

• Great work to drive on through all the way to the end :) One minor reordering required - the clues used in #10 need to come a little earlier in order for the two letters changed to O to be the actual centre of the string. There's also an erroneous Jonah-Judah mixup early on, but other than that this is an excellent answer!
– Stiv
Apr 5 at 18:30
• (Thanks, @GentlePutleRain, for the edit. I was about to edit and hope I haven't erased any of your edits.) Apr 5 at 20:27
• I used the "two letter pairs" as soon as it was possible. I noticed that the two letters were not exactly in the centre, but it was my last step and everything fell into place, so I didn't think about it too much. I had the first five or so steps this morning, but probably had manoeuvred myself to a dead end. I took up the puzzle again this evening and had Jonah stuck in my head and coudn't even reproduce my earlier steps. Eventually I saw my mistake, but when it came to writing everything up, Jonah crept into my mind again. Apr 5 at 20:33
• Anyway, a cool puzzle. It's fascinating to see how so many rather large and seemingly haphazard changes can take you from George Eliot via KSI, Radiohead and Charlemagne to Riemann. Apr 5 at 20:35
• Thanks @MOehm - I really liked this puzzle's mechanism but realised it was going to be a toughie - it's probably best it ended up having to be dropped from the series (I think its replacement fitted the general tone of the series a bit better), but I still wanted to share it here because I haven't seen this mechanism on PSE before. Thanks for persevering with it! :)
– Stiv
Apr 6 at 12:51