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A359455
Expansion of Sum_{k>0} x^k / (1 - x^(k^3)).
1
1, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 3, 3, 2, 2, 2, 2, 2, 2, 2, 3, 2, 3, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 3, 2, 3, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2
OFFSET
1,2
COMMENTS
Number of divisors d of n such that d^3 | (n - d).
LINKS
MATHEMATICA
a[n_] := DivisorSum[n, 1 &, Divisible[n-#, #^3] &]; Array[a, 100] (* Amiram Eldar, Aug 14 2023 *)
PROG
(PARI) a(n) = sumdiv(n, d, (n-d)%d^3==0);
CROSSREFS
Sequence in context: A100801 A194310 A306227 * A363853 A272231 A209253
KEYWORD
nonn,easy
AUTHOR
Seiichi Manyama, Jan 06 2023
STATUS
approved