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A372786
Number of divisors of 6n; a(n) = tau(6*n) = A000005(6*n).
11
4, 6, 6, 8, 8, 9, 8, 10, 8, 12, 8, 12, 8, 12, 12, 12, 8, 12, 8, 16, 12, 12, 8, 15, 12, 12, 10, 16, 8, 18, 8, 14, 12, 12, 16, 16, 8, 12, 12, 20, 8, 18, 8, 16, 16, 12, 8, 18, 12, 18, 12, 16, 8, 15, 16, 20, 12, 12, 8, 24, 8, 12, 16, 16, 16, 18, 8, 16, 12, 24, 8, 20
OFFSET
1,1
FORMULA
Sum_{k=1..n} a(k) ~ (15*n*(log(n) + 2*gamma - 1) + n*(5*log(2) + 3*log(3))) / 6, where gamma is the Euler-Mascheroni constant A001620.
MATHEMATICA
Table[DivisorSigma[0, 6*n], {n, 1, 150}]
PROG
(PARI) A372786(n) = numdiv(6*n); \\ Antti Karttunen, Jul 19 2024
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, May 13 2024
STATUS
approved