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%I #10 Dec 26 2018 11:52:49
%S 0,1,7,8,18,25,26,34,52,55,59,60,81,89,107,112,114,115,136,148,170,
%T 188,189,193,195,196,235,248,260,282,286,300,307,308,337,341,342,396,
%U 403,424,430,448,449,455,456,469,521,530,540,572,585,616,619,628,637,644,645,684,697
%N Numbers that are sums of consecutive heptagonal numbers (A000566).
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/HeptagonalNumber.html">Heptagonal Number</a>
%t terms = 59;
%t nmax = 17; kmax = 9; (* empirical *)
%t T = Table[n(5n-3)/2, {n, 0, nmax}];
%t Union[T, Table[k MovingAverage[T, k], {k, 2, kmax}]//Flatten][[1 ;; terms]] (* _Jean-François Alcover_, Dec 26 2018 *)
%Y Cf. A000566, A002413, A034705, A034706, A319184, A319185, A322637.
%K nonn
%O 1,3
%A _Ilya Gutkovskiy_, Dec 21 2018