A276729 Number of nonprime digits in the decimal expansion of n.

1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 2, 2, 1, 1, 2, 1, 2, 1, 2, 2, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 2, 2, 1, 1, 2, 1, 2, 1, 2, 2, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 2, 2, 1, 1, 2, 1, 2, 1, 2, 2, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 2, 2, 1, 1, 2, 1, 2, 1, 2, 2, 2

Offset: 0

Author

M. F. Hasler, Sep 16 2016

Keywords

• nonn
• base
• easy

Links

• Robert Israel, Table of n, a(n) for n = 0..10000

Crossrefs

Cf. A055642, A193238, A085557, A046034 (indices of 0's), A084984, A085558, A202267, A202268.

Cf. A011557 (integers that give records).

Programs

Maple

f:= proc(n) local t; option remember;
  t:= n mod 10;
procname((n-t)/10) + `if`(member(t,[2,3,5,7]),0,1)
end proc:
f(0):= 0:
1,seq(f(i),i=1..100); # Robert Israel, Feb 27 2019

PARI

a(n)=#select(t->!isprime(t),digits(n))

Formula

a(n) = A055642(n) - A193238(n).

a(A046034(n)) = 0. - Gordon Atkinson, Sep 06 2019