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A046841 Sum of divisors divides sum of cubes of divisors. 3
1, 2, 3, 5, 6, 7, 8, 10, 11, 12, 13, 14, 15, 16, 17, 19, 20, 21, 22, 23, 24, 26, 27, 29, 30, 31, 33, 34, 35, 37, 38, 39, 40, 41, 42, 43, 46, 47, 48, 51, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
A005117 (squarefree numbers) is a subsequence. - Ivan Neretin, Dec 20 2017
LINKS
EXAMPLE
2 is a term because 1+8 = 9 is divisible by 1+2 = 3.
x=208 is a term: The power sums of divisors for k=0,1,2,3 are as follows: 10,434,54970,10288838; and sigma(1,208)=434 divides sigma(3,208)=10288838=434*23707.
MATHEMATICA
Select[Range@ 85, Divisible[DivisorSigma[3, #], DivisorSigma[1, #]] &] (* Michael De Vlieger, Aug 01 2017 *)
PROG
(PARI) isA046841(n)=sigma(n, 3)%sigma(n, 1)==0 \\ Michael B. Porter, Apr 07 2010
CROSSREFS
Sequence in context: A175084 A171519 A072099 * A244218 A164514 A000037
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified May 19 05:44 EDT 2024. Contains 372666 sequences. (Running on oeis4.)