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 A375057 #7 Oct 10 2024 15:21:41
%S A375057 1,4,8,12,16,20,25,29,33,37,42,46,50,54,59,63,67,71,76,80,84,88,93,97,
%T A375057 101,105,110,114,118,122,127,131,135,140,144,148,152,157,161,165,169,
%U A375057 174,178,182,186,191,195,199,203,208,212,216,221,225,229,233,238
%N A375057 a(n) = least k such that (n*pi)^(2k)/(2 k)! < 1.
%C A375057 The numbers (n*Pi)^(2k)/(2 k)! are the coefficients in the Maclaurin series for cos x when x = n*Pi.
%C A375057 (n*pi)^k/(2 k)! < 1 for every k >= a(n).
%t A375057 a[n_] := Select[Range[300], (n Pi)^(2 #)/(2 #)! < 1 &, 1]
%t A375057 Flatten[Table[a[n], {n, 0, 300}]]
%Y A375057 Cf. A374987, A376456, A376457, A375053, A375054.
%K A375057 nonn
%O A375057 0,2
%A A375057 _Clark Kimberling_, Oct 01 2024
%E A375057 Edited by _Clark Kimberling_, Oct 10 2024