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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 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: A100382 A292448 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 September 17 11:15 EDT 2019. Contains 327129 sequences. (Running on oeis4.)