login
Smallest positive integer requiring n syllables to pronounce in American English.
3

%I #27 May 27 2024 22:37:30

%S 1,7,11,27,77,111,127,177,777,1127,1177,1777,7777,11777,27777,77777,

%T 111777,127777,177777,777777,1127777,1177777,1777777,7777777,11777777,

%U 27777777,77777777,111777777,127777777,177777777,777777777,1127777777,1177777777,1777777777

%N Smallest positive integer requiring n syllables to pronounce in American English.

%C Assumes the American usage of billion, trillion, etc. ("short scale"), which makes a difference from a(59) on.

%C See A002810 for the British English version, which in particular includes the additional "and", e.g., in "one hundred and seven". Therefore the sequences differ from a(6)=111 on, with A002810(6)= 107. - _M. F. Hasler_, Nov 03 2013

%H Robert G. Wilson v, <a href="/A000027/a000027.txt">English names for the numbers from 0 to 11159 without spaces or hyphens</a>.

%H <a href="/index/El#English">Index to OEIS: sequences related to English words for n</a>

%F a(n) = min{ k | A075774(k)=n }. - _M. F. Hasler_, Nov 03 2013

%F a(n+11) = a(n)*1000+777, as long as a(n+11) is less than one quadrillion (whatever scale is used). - _M. F. Hasler_, Nov 03 2013

%o (PARI) A045736(n)={n>11 || for(k=1,1e5,A075774(k)==n && return(k)); A045736(n-11*n=(n-1)\11)*1000^n+1000^n\9*7 } \\ This code is valid up to n=58 (short scale) or n=82 (long scale). - _M. F. Hasler_, Nov 03 2013

%Y Cf. A002810.

%K nonn,word

%O 1,2

%A _Brian Galebach_