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.
%I A339086 #5 Nov 23 2020 17:08:36 %S A339086 1,1,0,0,0,0,1,2,0,0,0,1,2,0,0,0,1,4,6,0,0,1,4,6,0,0,1,6,12,0,0,1,6, %T A339086 18,24,0,1,8,24,24,0,1,8,30,48,0,1,10,42,72,0,1,10,48,120,120,1,12,60, %U A339086 144,120,1,12,72,216,240,1,14,84,264,360,1,14,96,360,600,1,16,114 %N A339086 Number of compositions (ordered partitions) of n into distinct parts congruent to 1 mod 5. %H A339086 <a href="/index/Com#comp">Index entries for sequences related to compositions</a> %F A339086 G.f.: Sum_{k>=0} k! * x^(k*(5*k - 3)/2) / Product_{j=1..k} (1 - x^(5*j)). %e A339086 a(18) = 6 because we have [11, 6, 1], [11, 1, 6], [6, 11, 1], [6, 1, 11], [1, 11, 6] and [1, 6, 11]. %t A339086 nmax = 78; CoefficientList[Series[Sum[k! x^(k (5 k - 3)/2)/Product[1 - x^(5 j), {j, 1, k}], {k, 0, nmax}], {x, 0, nmax}], x] %Y A339086 Cf. A003520, A016861, A032020, A032021, A109697, A280454, A337547, A337548, A339059, A339060, A339087, A339088, A339089. %K A339086 nonn %O A339086 0,8 %A A339086 _Ilya Gutkovskiy_, Nov 23 2020