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Number of partitions of n into sums of exactly three distinct powers of 2.
5

%I #10 Aug 01 2023 06:56:10

%S 0,0,0,0,0,0,1,0,0,0,1,0,1,2,0,0,0,1,1,1,3,2,0,1,3,3,2,5,2,1,1,5,6,3,

%T 9,5,4,5,10,9,8,13,8,10,8,16,17,15,22,18,18,20,25,28,27,34,31,32,33,

%U 44,49,44,64,53,56,61,71,77,77,100,88,94,99,123,125,132,162,147,154

%N Number of partitions of n into sums of exactly three distinct powers of 2.

%H David A. Corneth, <a href="/A091890/b091890.txt">Table of n, a(n) for n = 1..10000</a>

%e a(14)=2: 14 = (2^3+2^2+2^1) = (2^2+2^1+2^0)+(2^2+2^1+2^0).

%t With[{max = 80}, m = Select[Range[max], DigitCount[#, 2, 1] == 3 &]; a[n_] := Length@ IntegerPartitions[n, n, m]; Array[a, max]] (* _Amiram Eldar_, Aug 01 2023 *)

%Y Cf. A014311, A018819, A091889, A000120, A000041, A091893, A091891.

%K nonn

%O 1,14

%A _Reinhard Zumkeller_, Feb 10 2004