A192438 Number of bases <= n in which n has no digits exceeding 9.

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 20, 21, 21, 22, 22, 23, 23, 24, 24, 25, 25, 25, 26, 26, 26, 27, 27, 27, 28, 28, 28, 29, 28, 29, 30, 29, 29, 31, 30, 30, 31, 31, 31, 31, 31, 32, 33, 31, 31, 34, 33, 32, 33, 33

Offset

1,2

Links

Table of n, a(n) for n=1..64.

Example

30 is 1E, 1D, 1C, 1B, 1A in bases 16 through 20, while in other bases it uses only decimal digits. Thus a(30) = 30 - 5 = 25.

Prog

(PARI) a(n)=my(m, k); 1+sum(b=2, n, k=n; m=1; while(k, if(k%b>9, m=0; break); k\=b); m)

Crossrefs

Sequence in context: A323366 A030066 A355479 * A081331 A369261 A369260

Adjacent sequences: A192435 A192436 A192437 * A192439 A192440 A192441

Keyword

nonn,base

Author

Vladimir Shevelev and Charles R Greathouse IV, Jul 01 2011

Status

approved