A077268 Number of bases in which n requires at least one zero to be written.

0, 1, 1, 2, 2, 3, 1, 3, 3, 4, 3, 5, 2, 3, 3, 4, 3, 6, 4, 6, 4, 3, 2, 7, 3, 4, 5, 7, 4, 7, 2, 6, 5, 5, 6, 8, 4, 5, 5, 8, 3, 7, 2, 5, 6, 4, 3, 9, 4, 7, 7, 7, 4, 9, 6, 8, 4, 4, 3, 11, 3, 4, 5, 7, 7, 9, 4, 6, 6, 9, 4, 11, 5, 6, 8, 7, 7, 9, 4, 9, 6, 6, 5, 12, 6, 5, 5, 9, 4, 11, 5, 6, 4, 4, 5, 11, 4, 7, 8, 10, 6

Offset: 1

Author

Henry Bottomley, Nov 01 2002

Keywords

• base
• nonn

Examples

			a(9)=3 since it requires zeros when written in bases 2, 3 or 9 (as 1001, 100 or 10 respectively).
		

Links

• Eric M. Schmidt, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A033093, A062842, A077266, A077267.

Programs

PARI

a(n) = sum(i=2, n, ! vecmin(digits(n, i))); \\ Michel Marcus, Jul 09 2014

Sage

def A077268(n) : return sum(0 in n.digits(m) for m in range(2,n+1)) # Eric M. Schmidt, Jul 09 2014