cp's OEIS Frontend

A132363 Least natural number in English which requires exactly n characters to spell including spaces and hyphens, or 0 if no such number exists. The inverse of A052360.

%I A132363 #10 Feb 16 2025 08:33:06
%S A132363 1,0,3,11,15,13,17,21,24,23,73,3000,101,104,103,111,115,113,117,121,
%T A132363 124,123,173,323,373,1101,1104,1103,1111,1115,1113,1117,1121,1124,
%U A132363 1123,1173,1323,1373,3323,3373,11373,13323,13373,17373,21373,23323,23373,73373
%N A132363 Least natural number in English which requires exactly n characters to spell including spaces and hyphens, or 0 if no such number exists. The inverse of A052360.
%C A132363 This is to A052360 as A134629 is to A005589. Also assumes no 'and' is used to spell integers. This deviates from A134629 at a(10). "twenty-one" is the smallest integer whose standard English name has a hyphen. "one hundred" is the smallest integer whose standard English name has a space. "one hundred twenty-one" is the smallest integer whose standard English name has a space and a hyphen.
%H A132363 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Number.html">Number</a>
%e A132363 a(3) = 1 because "one" has 3 characters.
%e A132363 a(4) = 0 because "zero" has 4 characters.
%e A132363 a(5) = 3 because "three" has 5 characters.
%e A132363 a(6) = 11 because "eleven" has 6 characters.
%e A132363 a(7) = 15 because "fifteen" has 7 characters.
%e A132363 a(8) = 13 because "thirteen" has 8 characters.
%e A132363 a(9) = 17 because "seventeen" has 9 characters.
%e A132363 a(10) = 21 because "twenty-one" has 10 characters.
%e A132363 a(11) = 24 because "twenty-four" has 11 characters.
%e A132363 a(12) = 23 because "twenty-three" has 12 characters.
%e A132363 a(13) = 73 because "seventy-three" has 13 characters.
%e A132363 a(14) = 3000 because "three thousand" has 14 characters.
%Y A132363 Cf. A005589, A052360, A119960, A129774, A134629.
%K A132363 easy,nonn,word
%O A132363 3,3
%A A132363 _Jonathan Vos Post_, Nov 08 2007
%E A132363 Corrected and extended by _Martin Fuller_, Nov 24 2007