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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A326668 Number of strict factorizations of 2^n into factors > 1 with integer average.

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%I A326668 #4 Jul 18 2019 06:18:41
%S A326668 1,1,2,2,3,3,4,4,6,5,7,7,9,9,12,12,17,17,21,24,33,33,42,46,63,61,81,
%T A326668 82,118,106,149,137,213,172,263,221,363,266,453,335,594,409,735,484,
%U A326668 968,594,1139,731,1486,813,1801,1026,2177,1230,2667,1348,3334,1693
%N A326668 Number of strict factorizations of 2^n into factors > 1 with integer average.
%C A326668 Also the number of strict integer partitions y of n such that the average of the set {2^s: s in y} is an integer.
%e A326668 The a(1) = 1 through a(11) = 7 partitions (A = 10, B = 11):
%e A326668   (1)  (2)  (3)   (4)   (5)   (6)   (7)   (8)   (9)    (A)   (B)
%e A326668             (21)  (31)  (32)  (42)  (43)  (53)  (54)   (64)  (65)
%e A326668                         (41)  (51)  (52)  (62)  (63)   (73)  (74)
%e A326668                                     (61)  (71)  (72)   (82)  (83)
%e A326668                                                 (81)   (91)  (92)
%e A326668                                                 (531)        (A1)
%e A326668                                                              (731)
%t A326668 Table[Length[Select[IntegerPartitions[n],UnsameQ@@#&&IntegerQ[Mean[2^#]]&]],{n,30}]
%Y A326668 The non-strict case is A326667.
%Y A326668 Factorizations with integer average are A326622.
%Y A326668 Strict partitions with integer average are A102627.
%Y A326668 Subsets with integer average are A051293.
%Y A326668 Cf. A001055, A067538, A102627, A326028, A326647, A326666, A326670, A326671.
%K A326668 nonn
%O A326668 1,3
%A A326668 _Gus Wiseman_, Jul 17 2019