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A371909
Number of divisors of the partial sums of A109890.
3
1, 2, 4, 6, 5, 8, 9, 6, 6, 12, 6, 9, 16, 15, 12, 14, 20, 16, 18, 15, 8, 12, 4, 8, 8, 8, 12, 16, 12, 8, 8, 12, 12, 16, 16, 8, 48, 8, 8, 8, 16, 20, 8, 16, 48, 12, 4, 16, 4, 12, 8, 8, 18, 16, 60, 12, 20, 8, 24, 24, 15, 36, 40, 36, 12, 8, 20, 32, 8, 12, 36, 16, 24
OFFSET
1,2
LINKS
FORMULA
a(n) = A000005(A109735(n)).
MATHEMATICA
nn = 120; c[_] := False;
Array[Set[{a[#], c[#]}, {#, True}] &, 2]; s = a[1] + a[2];
{1}~Join~Reap[Do[k = SelectFirst[Divisors[s], ! c[#] &];
c[k] = True; Sow[DivisorSigma[0, s]];
s += k, {n, 3, nn}] ][[-1, 1]]
CROSSREFS
KEYWORD
nonn
AUTHOR
Michael De Vlieger, Apr 26 2024
STATUS
approved