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A195052 Number of divisors of 24*n - 1 divided by 2. 2
1, 1, 1, 2, 2, 2, 1, 1, 2, 1, 1, 2, 1, 2, 1, 1, 2, 1, 4, 1, 1, 2, 2, 3, 1, 2, 1, 2, 2, 1, 1, 2, 2, 2, 1, 1, 1, 1, 4, 2, 1, 2, 1, 2, 2, 1, 3, 1, 3, 2, 1, 2, 2, 4, 1, 2, 1, 2, 2, 1, 4, 1, 1, 2, 1, 1, 1, 2, 2, 2, 2, 2, 2, 3, 2, 1, 1, 1, 2, 2, 2, 2, 2, 4, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,4
COMMENTS
It appears that this sequence has the same parity as the spt function A092269 (See A195053). - Omar E. Pol, Jan 30 2012
LINKS
George E. Andrews, Frank G. Garvan, and Jie Liang, Self-conjugate vector partitions and the parity of the spt-function, Acta Arith., Vol. 158, No. 3 (2013), pp. 199-218; alternative link; author's link.
FORMULA
a(n) = A000005(A183010(n))/2 = A195051(n)/2.
Sum_{k=1..n} a(k) ~ (n/6) * (log(n) + 2*gamma - 1 + 5*log(2) + 2*log(3)), where gamma is Euler's constant (A001620). - Amiram Eldar, Dec 22 2023
MATHEMATICA
a[n_] := DivisorSigma[0, 24*n-1]/2; Array[a, 100] (* Amiram Eldar, Dec 22 2023 *)
PROG
(PARI) a(n) = numdiv(24*n-1)/2; \\ Amiram Eldar, Dec 22 2023
CROSSREFS
Sequence in context: A213366 A212648 A255507 * A104637 A188795 A325444
KEYWORD
nonn,easy
AUTHOR
Omar E. Pol, Jan 13 2012
STATUS
approved

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Last modified March 18 22:56 EDT 2024. Contains 370952 sequences. (Running on oeis4.)