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%I #15 Apr 27 2023 12:47:11
%S 0,1,15,105,436,1367,3539,8033,16475,31275,55748,94425,153192,239691,
%T 363446,536375,772909,1090592,1510201,2056462,2758123,3648814,4767088,
%U 6157387,7870067,9962502,12499033,15552247,19202869,23541165,28666799,34690401,41733315
%N Number of partitions of 7n into 7 parts.
%H Ray Chandler, <a href="/A256287/b256287.txt">Table of n, a(n) for n = 0..50</a>
%H <a href="/index/Rec#order_22">Index entries for linear recurrences with constant coefficients</a>, signature (2, 0, -1, 0, -1, 1, -2, 2, 1, 0, 0, 0, -1, -2, 2, -1, 1, 0, 1, 0, -2, 1).
%e For n=2, the 15 partitions of 14 are [1,1,1,1,1,1,8], [1,1,1,1,1,2,7], ..., [1,2,2,2,2,2,3], [2,2,2,2,2,2,2].
%t Length /@ (Total /@ IntegerPartitions[7 #, {7}] & /@ Range[0, 24]) (* _Michael De Vlieger_, Mar 21 2015 *)
%o (PARI) concat(0, vector(35, n, k=0; forpart(p=7*n, k++, , [7,7]); k))
%Y Cf. A235988, A238340, A256225, A256226, A256288.
%K nonn,easy
%O 0,3
%A _Colin Barker_, Mar 21 2015