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%I #17 May 17 2021 08:49:42
%S 1,1045,5985
%N a(n) is the least integer that can be expressed as the sum of one or more consecutive nonzero octagonal numbers in exactly n ways.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/OctagonalNumber.html">Octagonal Number</a>
%H <a href="/index/Pol#polygonal_numbers">Index to sequences related to polygonal numbers</a>
%e From _Seiichi Manyama_, May 16 2021: (Start)
%e Let S(k, m) denote the sum of m octagonal numbers starting from k*(3*k-2). We have
%e a(1) = S(1, 1);
%e a(2) = S(19, 1) = S(1, 10);
%e a(3) = S(45, 1) = S(11, 9) = S(1, 18). (End)
%Y Cf. A000567, A054859, A068314, A186337, A298467, A322637, A334007, A334008, A334010, A334011, A344376.
%K nonn,hard,more
%O 1,2
%A _Ilya Gutkovskiy_, Apr 12 2020