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Numbers that are sums of consecutive centered heptagonal numbers (A069099).
5

%I #11 Dec 27 2018 07:59:13

%S 0,1,8,9,22,30,31,43,65,71,73,74,106,114,136,144,145,148,177,197,220,

%T 242,250,251,253,254,316,325,345,368,386,390,398,399,450,451,463,522,

%U 547,565,569,587,595,596,598,638,702,704,736,766,775,818,840,841,848,849,914,953

%N Numbers that are sums of consecutive centered heptagonal numbers (A069099).

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Centered_heptagonal_number">Centered heptagonal number</a>

%t terms = 58;

%t nmax = 17; kmax = 8; (* empirical *)

%t T = Table[(7 n^2 - 7 n + 2)/2, {n, 1, nmax}];

%t Union[{0}, T, Table[k MovingAverage[T, k], {k, 2, kmax}] // Flatten][[1 ;; terms]] (* _Jean-François Alcover_, Dec 27 2018 *)

%Y Cf. A004126, A069099, A152043, A322610, A322611, A322636, A322638, A320728.

%K nonn

%O 1,3

%A _Ilya Gutkovskiy_, Dec 21 2018