A072686 Prime numbers whose (British) English names have a prime number of letters.

2, 3, 7, 23, 37, 79, 83, 97, 109, 139, 157, 163, 167, 199, 211, 229, 239, 257, 263, 271, 313, 401, 421, 431, 449, 491, 503, 521, 569, 643, 647, 653, 709, 719, 751, 761, 809, 907, 991, 1021, 1031, 1049, 1069, 1091, 1103, 1301, 1303, 1307, 1327, 1409, 1511

Offset

0,1

Comments

See A231075 for the American English version. The sequences coincide up to a(8)=97 but are then completely different, due to the additional "and" (e.g. in "one hundred and nine") in the British style. - M. F. Hasler, Nov 03 2013

Links

Table of n, a(n) for n=0..50.

Index entries for sequences related to number of letters in n

Example

e.g. 2003 -> "TWOTHOUSANDANDTHREE" -> 19 letters and 19 is prime. Note that the "and" naming convention is used; e.g. "ONE HUNDRED AND ONE", "ONE THOUSAND NINE HUNDRED AND SEVENTY THREE".

Crossrefs

Prime elements of A072685.

Sequence in context: A059661 A214704 A231075 * A002230 A106865 A267504

Adjacent sequences: A072683 A072684 A072685 * A072687 A072688 A072689

Keyword

easy,nonn,word

Author

Mark Hudson (mrmarkhudson(AT)hotmail.com), Jul 02 2002

Status

approved