A014869 - OEIS

%I #18 Aug 08 2021 11:34:23

%S 1,3,9,19,27,57,81,171,243,381,513,729,1143,1539,2187,3429,4617,4707,

%T 6561,7239,10287,13053,13149,13851,14121,19683,21717,30861,39159,

%U 39447,41553,42363,48387,59049,65151,89433,92583,117477,118341,124659,127089,145161,177147

%N Numbers k that divide s(k), where s(1)=1, s(j)=19*s(j-1)+j.

%t nxt[{n_,a_}]:={n+1,19a+n+1}; Transpose[Select[NestList[nxt,{1,1},70000], Divisible[Last[#],First[#]]&]][[1]] (* _Harvey P. Dale_, Jan 21 2015 *)

%o (PARI) lista(nn) = my(s); for(k=1, nn, s=19*s+k; if(s%k==0, print1(k, ", "))); \\ _Jinyuan Wang_, Aug 08 2021

%Y s(n) = A014903(n).

%K nonn

%O 1,2

%A _N. J. A. Sloane_, _Olivier Gérard_

%E More terms from _Jinyuan Wang_, Aug 08 2021