A169665 Numbers divisible by the sum of 4th powers of their digits.

1, 10, 100, 102, 110, 111, 1000, 1010, 1011, 1020, 1100, 1101, 1110, 1121, 1122, 1634, 2000, 2322, 4104, 5000, 8208, 9474, 10000, 10010, 10011, 10100, 10101, 10110, 10200, 10412, 11000, 11001, 11010, 11100, 11210, 11220, 12502, 12521, 14758

Offset

1,2

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Digit.

Formula

Numbers k such that A055013(k) | k.

Example

12521 is a term since 1^4 + 2^4 + 5^4 + 2^4 + 1^4 = 659, and 12521 = 19*659;
89295 is a term since 8^4 + 9^4 + 2^4 + 9^4 + 5^4 = 17859, and 89295 = 5*17859.

Maple

A:= proc(n) add(d^4, d=convert(n, base, 10)) ; end proc: for n from 1 to 200000 do:if irem( n, A(n))=0 then printf(`%d, `, n):else fi:od:

Mathematica

Select[Range[15000], Divisible[#, Plus @@ (IntegerDigits[#]^4)] &] (* Amiram Eldar, Jan 31 2021 *)

Crossrefs

Cf. A034087, A034088, A055013, A169666.

Sequence in context: A336611 A342215 A342135 * A257795 A257950 A052009

Adjacent sequences: A169662 A169663 A169664 * A169666 A169667 A169668

Keyword

nonn,base

Author

Michel Lagneau, Apr 05 2010

Status

approved