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A169665
Numbers divisible by the sum of 4th powers of their digits.
6
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
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
KEYWORD
nonn,base
AUTHOR
Michel Lagneau, Apr 05 2010
STATUS
approved