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a(n) = Product_{i=0..7} floor((n+i)/8).
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%I #30 Jan 10 2023 01:49:04

%S 0,0,0,0,0,0,0,0,1,2,4,8,16,32,64,128,256,384,576,864,1296,1944,2916,

%T 4374,6561,8748,11664,15552,20736,27648,36864,49152,65536,81920,

%U 102400,128000,160000,200000,250000,312500

%N a(n) = Product_{i=0..7} floor((n+i)/8).

%C For n >= 8, a(n) is the maximal product of eight positive integers with sum n. - _Wesley Ivan Hurt_, Jul 08 2022

%C A quasipolynomial of order 8 and degree 8. - _Charles R Greathouse IV_, Nov 06 2022

%H <a href="/index/Rec#order_58">Index entries for linear recurrences with constant coefficients</a>, signature (2, -1, 0, 0, 0, 0, 0, 7, -14, 7, 0, 0, 0, 0, 0, -21, 42, -21, 0, 0, 0, 0, 0, 35, -70, 35, 0, 0, 0, 0, 0, -35, 70, -35, 0, 0, 0, 0, 0, 21, -42, 21, 0, 0, 0, 0, 0, -7, 14, -7, 0, 0, 0, 0, 0, 1, -2, 1).

%F a(8*n) = n^8 (A001016). - _Bernard Schott_, Nov 06 2022

%F a(n) = n^8/8^8 + O(n^6). - _Charles R Greathouse IV_, Nov 06 2022

%F Sum_{n>=8} 1/a(n) = 1 + zeta(8). - _Amiram Eldar_, Jan 10 2023

%t Table[Product[Floor[(n+i)/8],{i,0,7}],{n,0,40}] (* _Harvey P. Dale_, Nov 13 2013 *)

%o (PARI) a(n) = prod(i=0, 7, (n+i)\8); \\ _Michel Marcus_, Jul 14 2022

%Y Maximal product of k positive integers with sum n, for k = 2..10: A002620 (k=2), A006501 (k=3), A008233 (k=4), A008382 (k=5), A008881 (k=6), A009641 (k=7), this sequence (k=8), A009714 (k=9), A354600 (k=10).

%Y Cf. A001016, A013666.

%K nonn,easy

%O 0,10

%A _N. J. A. Sloane_