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A152981 Sum of divisors of Motzkin number A001006(n). 3
1, 1, 3, 7, 13, 32, 72, 128, 360, 1008, 3836, 9408, 15512, 66960, 252720, 785148, 1137960, 3340800, 13072776, 42465024, 69530400, 238761600, 678562560, 2412043920, 5270534880, 10943277120, 44922182340, 117229255200, 209990825568, 623486730240, 1698651339840, 7019676332760, 18578092462280 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..32.

FORMULA

a(n) = sigma(A001006(n)) = A000203(A001006(n)).

MAPLE

A152981 := proc(n) numtheory[sigma](A001006(n)) ; end proc:

seq(A152981(n), n=0..40) ; # R. J. Mathar, Jul 08 2011

CROSSREFS

Cf. A000005, A000203, A001006, A152761.

Sequence in context: A023195 A100382 A222227 * A112040 A222187 A084611

Adjacent sequences:  A152978 A152979 A152980 * A152982 A152983 A152984

KEYWORD

nonn

AUTHOR

Omar E. Pol, Dec 20 2008

STATUS

approved

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Last modified December 4 19:31 EST 2016. Contains 278755 sequences.