A164794 a(n) is the smallest number whose English name has the letter "f" in the n-th position, or -1 if no such number exists.

4, -1, 15, -1, -1, 44, 24, 74, -1, -1, 104, 404, 115, 415, 315, 144, 124, 174, 324, 374, 3074, 1104, 1404, 1115, 1415, 1315, 1144, 1124, 1174, 1324, 1374, 3324, 3374, 11374, 13324, 13374, 17374, 23324, 23374, 73374, 101374, 103324, 103374, 111374, 113324

Offset

1,1

Links

Table of n, a(n) for n=1..45.

Example

a(1)=4 ("Four"), a(3)=15 ("fiFteen"), a(11)=104 ("onehundredFour").

Crossrefs

Cf. A164789 ("o"), A164790 ("e"), A164791 ("n"), A164792 ("t").

Cf. A164793 ("i"), A164795 ("h"), A164796 ("r"), A164797 ("u").

Sequence in context: A096644 A145829 A016115 * A353763 A226478 A349124

Adjacent sequences: A164791 A164792 A164793 * A164795 A164796 A164797

Keyword

word,sign

Author

Claudio Meller, Aug 26 2009

Extensions

a(21) and beyond from Michael S. Branicky, Feb 02 2021

Status

approved