A152761 Sum of divisors of Catalan number A000108(n).

1, 1, 3, 6, 24, 96, 336, 672, 3024, 9072, 35280, 120960, 483840, 1874880, 10108800, 20217600, 107827200, 398131200, 1919877120, 6051594240, 24710676480, 86487367680, 339771801600, 1141066967040, 4122564526080, 16784726999040

Offset

0,3

Links

Amiram Eldar, Table of n, a(n) for n = 0..1667

Formula

a(n) = sigma(A000108(n)) = A000203(A000108(n)).

a(n) = A152762(n) + A000108(n). - R. J. Mathar, Jan 08 2009

Maple

with(numtheory): seq(sigma(binomial(2*n, n)/(n+1)), n = 0 .. 25); # Emeric Deutsch, Jan 10 2009
A000108 := proc(n) binomial(2*n, n)/(n+1) ; end: A000203 := proc(n) numtheory[sigma](n) ; end: A152761 := proc(n) A000203(A000108(n)) ; end: for n from 0 to 30 do printf("%d, ", A152761(n)) ; od: # R. J. Mathar, Jan 08 2009

Mathematica

DivisorSigma[1, CatalanNumber[Range[0, 30]]] (* Harvey P. Dale, Apr 17 2015 *)

Crossrefs

Cf. A000108, A000203.

Sequence in context: A363016 A327643 A296215 * A295761 A262349 A109155

Adjacent sequences: A152758 A152759 A152760 * A152762 A152763 A152764

Keyword

easy,nonn

Author

Omar E. Pol, Dec 14 2008

Extensions

Extended by R. J. Mathar and Emeric Deutsch, Jan 08 2009

Status

approved