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 A367808 #8 Dec 01 2023 18:50:46
%S A367808 1,4,19,103,634,4393,33893,288158,2674849,26888251,290614732,
%T A367808 3356438587,41203019361,535141595208,7324289215167,105271669493307,
%U A367808 1584113665608394,24890073684310405,407378999173905545,6930779764599424550,122334506551009552893,2236412875771806004767
%N A367808 a(n) = Sum_{k=0..n} A011971(n, k) * 2^(n - k).
%C A367808 The Peirce/Aitken polynomials evaluated at 1/2 and the result normalized with 2^n.
%o A367808 (Python)
%o A367808 from functools import cache
%o A367808 @cache
%o A367808 def b(n: int) -> list[int]:
%o A367808 if n == 0: return [1]
%o A367808 row = [b(n - 1)[n - 1]] + b(n - 1)
%o A367808 for k in range(1, n + 1): row[k] += row[k - 1]
%o A367808 return row
%o A367808 def a(n): return sum(b(n)[k] * 2 ** (n - k) for k in range(n + 1))
%o A367808 print([a(n) for n in range(22)])
%Y A367808 Cf. A011971, A367809.
%K A367808 nonn
%O A367808 0,2
%A A367808 _Peter Luschny_, Dec 01 2023