cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A008881 a(n) = Product_{j=0..5} floor((n+j)/6).

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%I A008881 #37 Jan 10 2023 01:48:48
%S A008881 0,0,0,0,0,0,1,2,4,8,16,32,64,96,144,216,324,486,729,972,1296,1728,
%T A008881 2304,3072,4096,5120,6400,8000,10000,12500,15625,18750,22500,27000,
%U A008881 32400,38880,46656,54432,63504,74088,86436,100842,117649,134456,153664,175616,200704
%N A008881 a(n) = Product_{j=0..5} floor((n+j)/6).
%C A008881 For n >= 6, a(n) is the maximal product of 6 positive integers with sum n. - _Wesley Ivan Hurt_, Jun 29 2022
%C A008881 The maximal product of k positive variables when their sum is equal to s is obtained when each term = s/k; hence, a(6m) = m^6 (A001014). - _Bernard Schott_, Jul 28 2022
%H A008881 G. C. Greubel, <a href="/A008881/b008881.txt">Table of n, a(n) for n = 0..1000</a>
%H A008881 <a href="/index/Rec#order_32">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1,0,0,0,5,-10,5,0,0,0,-10,20,-10,0,0,0,10,-20,10,0,0,0,-5,10,-5,0,0,0,1,-2,1).
%F A008881 Sum_{n>=6} 1/a(n) = 1 + zeta(6). - _Amiram Eldar_, Jan 10 2023
%p A008881 seq( mul( floor((n+i)/6), i=0..5 ), n=0..80);
%t A008881 Product[Floor[(Range[51]+j-2)/6], {j,6}] (* _G. C. Greubel_, Sep 13 2019 *)
%o A008881 (PARI) vector(50, n, prod(j=0,5, (n+j)\6) ) \\ _G. C. Greubel_, Sep 13 2019
%o A008881 (Magma) [(&*[Floor((n+j)/6): j in [0..5]]): n in [0..50]]; // _G. C. Greubel_, Sep 13 2019
%o A008881 (Sage) [product(floor((n+j)/6) for j in (0..5)) for n in (0..50)] # _G. C. Greubel_, Sep 13 2019
%o A008881 (GAP) List([0..50], n-> Product([0..5], j-> Int((n+j)/6))); # _G. C. Greubel_, Sep 13 2019
%Y A008881 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), this sequence (k=6), A009641 (k=7), A009694 (k=8), A009714 (k=9), A354600 (k=10).
%Y A008881 Cf. A001014 (6th power), A008588 (multiples of 6), A013664.
%K A008881 nonn,easy
%O A008881 0,8
%A A008881 _N. J. A. Sloane_