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Number of partitions of the n-th abundant number into abundant numbers.
3

%I #6 Aug 02 2019 12:59:57

%S 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,

%T 125,175,203,275,326,243,434,519,675,477,806,1044,1244,985,1604,1902,

%U 2420,1892,2887,2391,3632,2932,4342,5424,4509,6460,5513,8021,9557,11817

%N Number of partitions of the n-th abundant number into abundant numbers.

%H Amiram Eldar, <a href="/A097800/b097800.txt">Table of n, a(n) for n = 1..10000</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/AbundantNumber.html">Abundant Number</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Partition.html">Partition</a>

%e a(8)=4: A005101(8)=42 = A005101(5)+A005101(1)=30+12 =

%e A005101(4)+A005101(2)=24+18 = A005101(2)+2*A005101(1)=18+12+12.

%t 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 *)

%Y Cf. A005101, A000041, A097798, A097799.

%K nonn

%O 1,4

%A _Reinhard Zumkeller_, Aug 25 2004