Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #45 Jun 27 2020 01:15:19
%S 1,7,13,15,19,31,27,32,53,39,43,63,52,55
%N a(n) is the smallest k such that {1^2, 2^2, 3^2, ..., k^2} can be partitioned into n sets of equal sums.
%e For n = 1 the set is {1}
%e For n = 2 the sets are {1,2,4,7}, {3,5,6}.
%e For n = 3 the sets are {2,10,13}, {4,7,8,12}, {1,3,5,6,9,11}.
%e For n = 4 the sets are {2,9,15}, {1,7,8,14}, {4,5,10,13}, {3,6,11,12}.
%e For n = 5 the sets are {4,6,9,19}, {1,13,18}, {3,14,17}, {2,7,8,11,16}, {5,10,12,15}.
%e For n = 6 the sets are {1,3,6,27,31}, {4,12,26,30}, {5,7,14,25,29}, {2,8,20,22,28}, {9,13,15,18,19,24}, {10,11,16,17,21,23}.
%Y Cf. A019568, A240070, A330212.
%K nonn,more
%O 1,2
%A _Dean D. Ballard_, Jun 08 2020
%E a(12) from _Giovanni Resta_, Jun 08 2020
%E a(13)-a(14) from _Dean D. Ballard_, Jun 12 2020