OFFSET
1,2
COMMENTS
Numbers k such that k | A005258(k).
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..143
EXAMPLE
3 is a term since A005258(3) = 147 = 3 * 49 is divisible by 3.
MATHEMATICA
seq[kmax_] := Module[{ap0 = 1, ap1 = 3, ap2, s = {1}}, Do[ap2 = ((11*k^2 - 11*k + 3)*ap1 + (k-1)^2*ap0)/k^2; If[Divisible[ap2, k], AppendTo[s, k]]; ap0 = ap1; ap1 = ap2, {k, 2, kmax}]; s]; seq[5000]
PROG
(PARI) lista(kmax) = {my(ap0 = 1, ap1 = 3, ap2); print1("1, "); for(k = 2, kmax, ap2 = ((11*k^2 - 11*k + 3)*ap1 + (k-1)^2*ap0)/k^2; if(!(ap2 % k), print1(k, ", ")); ap0 = ap1; ap1 = ap2); }
CROSSREFS
KEYWORD
nonn
AUTHOR
Amiram Eldar, May 17 2024
STATUS
approved