A068596 - OEIS

A068596

Number of 4-ary Lyndon words whose trace and subtrace are both 0 mod 4.

1, 0, 1, 1, 11, 44, 169, 588, 1948, 6560, 23133, 84565, 317755, 1198336, 4509419, 16909184, 63409935, 238609052, 902444517, 3429249843, 13076666409, 49977802752, 191312873561, 733365845820, 2815437297416, 10825960652800, 41694907460224, 160823207301705

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,5

COMMENTS

The trace of a word is the sum of its characters; the subtrace of a word is the sum of all products of pairs of its characters.

LINKS

Table of n, a(n) for n=1..28.

Max Alekseyev, PARI/GP scripts for miscellaneous math problems

F. Ruskey, 4-ary Lyndon words with given trace and subtrace

CROSSREFS