OFFSET
1,2
COMMENTS
Numbers k such that k | A005259(k).
FORMULA
5 is a term since A005259(5) = 819005 = 5 * 163801 is divisible by 5.
MATHEMATICA
seq[kmax_] := Module[{ap0 = 1, ap1 = 5, ap2, s = {1}}, Do[ap2 = ((34*k^3 - 51*k^2 + 27*k - 5)*ap1 - (k-1)^3*ap0)/k^3; 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 = 5, ap2); print1("1, "); for(k = 2, kmax, ap2 = ((34*k^3 - 51*k^2 + 27*k - 5)*ap1 - (k-1)^3*ap0)/k^3; if(!(ap2 % k), print1(k, ", ")); ap0 = ap1; ap1 = ap2); }
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Amiram Eldar, May 17 2024
STATUS
approved