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%I #13 Feb 06 2017 08:48:52
%S 1,1,0,0,1,0,1,1,7,37,22,264,310,1181,2350,8102,38471,136528,738072,
%T 2811383,12163208,45121906,160620225,729516611,3962353196
%N Number of set partitions of [n] into subsets whose element sums are squares.
%e a(0) = 1: {}.
%e a(1) = 1: 1.
%e a(4) = 1: 1|234.
%e a(6) = 1: 1|2356|4.
%e a(7) = 1: 1|27|36|45.
%e a(8) = 7: 12345678, 1258|367|4, 1267|358|4, 1357|268|4, 13|268|457, 178|2356|4, 18|27|36|45.
%e a(10) = 22: 1|234|5678(10)|9, 1|23569|4|78(10), 1|2356|4|78(10)|9, 1|23578|4|69(10), 1|23578|4|6(10)|9, 1|23678(10)|45|9, 1|24578(10)|36|9, 1|27|34568(10)|9, 1|258(10)|3679|4, 1|258(10)|367|4|9, 1|258(10)|36|4|79, 1|259|36|4|78(10), 1|267(10)|3589|4, 1|267(10)|358|4|9, 1|2689|357(10)|4, 1|268|357(10)|4|9, 1|27|3589|4|6(10), 1|27|358|4|69(10), 1|27|358|4|6(10)|9, 1|2789(10)|36|45, 1|27|3689(10)|45, 1|27|36|4589(10).
%Y Cf. A000110, A278339, A281871.
%K nonn
%O 0,9
%A _Alois P. Heinz_, Feb 04 2017
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