In a certain code SEQUENCE is coded as FDOFVRFT. How is CHILDREN coded in that…

Concept: In a letter-shift coding pattern, every letter of the source word is shifted a fixed number of steps forward in the alphabet, and the resulting shifted letters are written in reverse order to form the code (equivalently, reversing the word first and then shifting each letter gives the same result, since the shift does not depend on letter position).

Application: Apply this to the given example, then to CHILDREN.

1. Reverse the code FDOFVRFT to get TFRVFODF, and line it up against SEQUENCE letter by letter: S to T, E to F, Q to R, U to V, E to F, N to O, C to D, E to F - every letter has moved forward by exactly one place in the alphabet.

2. So the rule is: shift each letter of the word forward by one place, then reverse the shifted string (or, equivalently, reverse the word first and shift each letter forward by one - both give the same result).

3. Reverse CHILDREN letter by letter: C-H-I-L-D-R-E-N becomes N-E-R-D-L-I-H-C.

4. Shift each letter of NERDLIHC forward by one place, as mapped below.

Reading the shifted column in order gives OFSEMJID.

Cross-check: Reversing OFSEMJID back gives DIJMESFO, and shifting each of those letters one place backward (D to C, I to H, J to I, M to L, E to D, S to R, F to E, O to N) restores CHILDREN exactly, confirming the transformation.

Result: CHILDREN is coded as OFSEMJID.