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 A284267 #17 Jun 02 2025 12:21:03
%S A284267 1,2,1,3,2,2,1,4,3,1,1,2,2,2,1,5,4,1,2,1,1,2,1,2,2,1,1,2,2,2,1,6,5,1,
%T A284267 2,2,2,1,1,1,1,1,1,2,2,2,1,2,2,1,2,1,1,2,1,2,2,1,1,2,2,2,1,7,6,1,2,2,
%U A284267 2,1,1,2,2,1,2,1,1,1,1,1,1,1,1,1,1,2,1,2,2,1,1,2,2,2,1,2,2,1,2,2,2,1,1,1,1,1,1,2,2,2,1,2,2,1,2,1,1,2,1,2,2
%N A284267 Number of terms with coefficient 1 in the Stern polynomial B(2n+1,x): a(n) = A056169(A277324(n)).
%C A284267 Number of 1's on row 2n+1 of table A125184.
%H A284267 Antti Karttunen, <a href="/A284267/b284267.txt">Table of n, a(n) for n = 0..8192</a>
%F A284267 a(n) = A284271((2*n)+1).
%F A284267 a(n) = A056169(A277324(n)).
%F A284267 Other identities. For all n >= 0:
%F A284267 A007306(1+n) = a(n) + A284268(n).
%t A284267 A003961[p_?PrimeQ] := A003961[p] = Prime[ PrimePi[p] + 1]; A003961[1] = 1; A003961[n_]:= A003961[n] = Times @@ (A003961[First[#]] ^ Last[#] & ) /@ FactorInteger[n] (* after _Jean-François Alcover_, Dec 01 2011 *); A260443[n_]:= If[n<2, n + 1, If[EvenQ[n], A003961[A260443[n/2]], A260443[(n - 1)/2] * A260443[(n + 1)/2]]]; a[n_]:= If[n<2, 0, Count[Transpose[FactorInteger[n]][[2]], 1]]; A277324[n_]:=A260443[2n + 1]; Table[a[A277324[n]], {n, 0, 150}] (* _Indranil Ghosh_, Mar 28 2017 *)
%o A284267 (PARI) A284267(n) = A284271(n+n+1); \\ Other code as in A284271.
%o A284267 (Scheme)
%o A284267 (define (A284267 n) (A284271 (+ n n 1)))
%o A284267 (define (A284267 n) (A056169 (A277324 n)))
%Y A284267 Cf. A007306, A056169, A125184, A260443, A277324, A284268.
%Y A284267 Odd bisection of A284271.
%K A284267 nonn
%O A284267 0,2
%A A284267 _Antti Karttunen_, Mar 25 2017