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.
From _Omar E. Pol_, Mar 01 2015: (Start) Written as an irregular triangle in which the row lengths are the terms of A011782, the sequence begins: 1; 6; 6,12; 6,16,12,24; 6,36,16,32,12,36,24,48; 6,36,36,72,16,56,32,64,12,72,36,72,24,68,48,96; 6,36,36,72,36,96,72,144,16,96,56,112,32,100,64,128,12,72,72,144,36,120,72,144,24,144,68,136... ... In each row the first quarter of the terms (and no more) are equal to 6 times the beginning of the sequence itself (corrected after Sloane's comment in A247649, Mar 03 2015). (End)
r1:=proc(f) local g,n; g:=n->nops(expand(f^n) mod 2); [seq(g(n),n=0..90)]; end; r1(1+x+x^2+x^3);
a[n_] := Count[CoefficientList[(1 + x + x^2 + x^3 + x^4 + x^5)^n, x], _?OddQ];
Table[a[n], {n, 0, 90}] (* Jean-François Alcover, Apr 06 2017 *)
a(n) = {my(pol=(1+x+x^2+x^3+x^4+x^5)*Mod(1,2)); subst(lift(pol^n), x, 1);} \\ Michel Marcus, Mar 01 2015
r1:=proc(f) local g,n; g:=n->nops(expand(f^n) mod 2); [seq(g(n),n=0..90)]; end; r1(1+x+x^2+x^4); # Alternative: P:= 1: for n from 0 to 100 do A[n]:= nops(P); P:= expand(P*(1+x+x^2+x^4)) mod 2; od: seq(A[i],i=0..100); # Robert Israel, Jan 07 2018
a[n_] := Count[(List @@ Expand[(1+x+x^2+x^4)^n]) /. x -> 1, _?OddQ]; a[0] = 1;
Table[a[n], {n, 0, 100}] (* Jean-François Alcover, Feb 06 2023 *)
a(n) = {my(pol=(1+x+x^2+x^4)*Mod(1,2)); subst(lift(pol^n), x, 1);} \\ Michel Marcus, Mar 01 2015
r1:=proc(f) local g,n; g:=n->nops(expand(f^n) mod 2); [seq(g(n),n=0..90)]; end; r1(1+x+x^2+x^3);
a[n_] := Count[(List @@ Expand[(1+x+x^3+x^4)^n]) /. x -> 1, _?OddQ]; a[0] = 1;
Table[a[n], {n, 0, 60}] (* Jean-François Alcover, Apr 04 2017 *)
a(n) = {my(pol=(1+x+x^3+x^4)*Mod(1,2)); subst(lift(pol^n), x, 1);} \\ Michel Marcus, Mar 01 2015
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