OFFSET
0,4
COMMENTS
Set k = n, take the k-th Xfactorial A048631(k) and find what is the maximum exponent h so that polynomial (X+1)^h still divides it (over GF(2), this can be computed with A268389, maybe also more directly). Set this h as a new value of k, and repeat. a(n) tells how many steps are needed before zero is reached.
Note that so far it is just an empirical observation that A268672(n) > 0 for all n > 0.
LINKS
Antti Karttunen, Table of n, a(n) for n = 0..65537
FORMULA
a(0) = 0, for n >= 1, a(n) = 1 + a(A268395(n)).
PROG
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 11 2016
STATUS
approved