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A097800
Number of partitions of the n-th abundant number into abundant numbers.
3
1, 1, 1, 2, 2, 4, 2, 4, 7, 8, 5, 14, 14, 5, 23, 26, 18, 38, 17, 46, 65, 34, 75, 50, 106, 59, 125, 175, 203, 275, 326, 243, 434, 519, 675, 477, 806, 1044, 1244, 985, 1604, 1902, 2420, 1892, 2887, 2391, 3632, 2932, 4342, 5424, 4509, 6460, 5513, 8021, 9557, 11817
OFFSET
1,4
LINKS
Eric Weisstein's World of Mathematics, Abundant Number
Eric Weisstein's World of Mathematics, Partition
EXAMPLE
a(8)=4: A005101(8)=42 = A005101(5)+A005101(1)=30+12 =
A005101(4)+A005101(2)=24+18 = A005101(2)+2*A005101(1)=18+12+12.
MATHEMATICA
n = 245; d = Select[Range[n], DivisorSigma[1, #] > 2 # &]; CoefficientList[ Series[1/Product[1 - x^d[[i]], {i, 1, Length[d]}], {x, 0, n}], x][[d + 1]] (* Amiram Eldar, Aug 02 2019 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Aug 25 2004
STATUS
approved