A008540 Numbers whose American English name contains the letter 'f'.

4, 5, 14, 15, 24, 25, 34, 35, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 64, 65, 74, 75, 84, 85, 94, 95, 104, 105, 114, 115, 124, 125, 134, 135, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn
• word

Links

• Paolo Xausa, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A008519 (o), A008520 (e), A008522 (t), A008536 (n), A008538 (s), A008553 (y).

Programs

Mathematica

A008540Q[n_]:=StringContainsQ[IntegerName[n,"Words"],"f"];Select[Range[0,200],A008540Q] (* Paolo Xausa, Aug 12 2023 *)

Extensions

Name edited by Paolo Xausa, Aug 12 2023