A376284 a(n) = least k such that (2n)^(2k)/(2 k)! < 1.

1, 2, 5, 7, 10, 13, 15, 18, 21, 24, 26, 29, 32, 34, 37, 40, 42, 45, 48, 51, 53, 56, 59, 61, 64, 67, 69, 72, 75, 78, 80, 83, 86, 88, 91, 94, 97, 99, 102, 105, 107, 110, 113, 116, 118, 121, 124, 126, 129, 132, 135, 137, 140, 143, 145, 148, 151, 154, 156, 159

Offset: 0

Author

Clark Kimberling, Oct 17 2024

Keywords

• nonn

Comments

The numbers (2n)^(2k)/(2 k)! are the coefficients in the Maclaurin series for cos x when x = 2. If m>a(n), then (2n)^(2k)/(2 k)! < 1.

Crossrefs

Cf. A370507, A376952, A376953, A376954, A376955, A376956, A376957, A376958, A376959, A376960.

Programs

Mathematica

a[n_] := Select[Range[200], (2n)^(2 #)/(2 #)! < 1 &, 1]
Flatten[Table[a[n], {n, 0, 200}]]