1,4

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

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

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

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

Cf. A033093, A062842, A077266, A077267.

Sequence in context: A071681 A135621 A224764 * A088741 A162911 A245327

Adjacent sequences: A077265 A077266 A077267 * A077269 A077270 A077271

base,nonn

Henry Bottomley, Nov 01 2002

approved