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a(n) = floor(binomial(n,8)/8).
1

%I #18 Jun 13 2023 11:11:32

%S 0,0,0,0,0,0,0,0,0,1,5,20,61,160,375,804,1608,3038,5469,9447,15746,

%T 25436,39971,61289,91933,135196,195284,277509,388513,536518,731615,

%U 986090,1314787,1735519,2269525,2941977

%N a(n) = floor(binomial(n,8)/8).

%H <a href="/index/Rec#order_65">Index entries for linear recurrences with constant coefficients</a>, signature (9, -36, 84, -126, 126, -84, 36, -10, 10, -36, 84, -126, 126, -84, 36, -10, 10, -36, 84, -126, 126, -84, 36, -10, 10, -36, 84, -126, 126, -84, 36, -10, 10, -36, 84, -126, 126, -84, 36, -10, 10, -36, 84, -126, 126, -84, 36, -10, 10, -36, 84, -126, 126, -84, 36, -10, 10, -36, 84, -126, 126, -84, 36, -9, 1).

%o (Sage) [floor(binomial(n,8)/8) for n in range(0,36)] # _Zerinvary Lajos_, Dec 01 2009

%o (PARI) a(n) = binomial(n, 8)\8; \\ _Michel Marcus_, Jan 28 2018

%Y A column of triangle A011857.

%K nonn

%O 0,11

%A _N. J. A. Sloane_