A014953 Numbers k such that k divides s(k), where s(1)=1, s(j) = s(j-1) + j*13^(j-1).

1, 3, 9, 27, 81, 183, 243, 549, 729, 1647, 2187, 4941, 6561, 11163, 14823, 19683, 33489, 44469, 59049, 67161, 100467, 133407, 177147, 201483, 301401, 400221, 531441, 604449, 680943, 736941, 870897, 904203, 1063611, 1200663, 1406721

Offset

1,2

Comments

From Robert Israel, Oct 07 2019: (Start)

Numbers k such that 144*k divides 1-(1-12*k)*13^k.

Contains all powers of 3 (A000244). (End)

Links

Table of n, a(n) for n=1..35.

Maple

filter:= proc(n) (1 - (1-12*n)*13 &^ n) mod (144*n) = 0 end proc:
select(filter, [$1..10^6]); # Robert Israel, Oct 07 2019

Mathematica

s[1]=1; s[n_]:=s[n]=s[n-1]+n*13^(n-1); Select[Range[1000], Divisible[s[#], #] &] (* Amiram Eldar, Nov 23 2018 *)

Crossrefs

Cf. A000244, A014928.

Sequence in context: A248960 A006521 A289257 * A274627 A080557 A022014

Adjacent sequences: A014950 A014951 A014952 * A014954 A014955 A014956

Keyword

nonn

Author

Olivier Gérard

Extensions

More terms from Sean A. Irvine, Nov 23 2018

Status

approved