A154521 The prime(n)-th digit of the concatenated positive nonprimes.

4, 6, 9, 0, 4, 5, 8, 0, 2, 6, 7, 2, 4, 5, 8, 2, 6, 8, 1, 4, 5, 8, 2, 5, 0, 4, 5, 7, 8, 1, 0, 2, 5, 6, 2, 0, 0, 1, 1, 4, 6, 1, 0, 2, 2, 2, 2, 3, 4, 3, 6, 0, 4, 4, 6, 8, 2, 5, 5, 6, 5, 1, 6, 9, 7, 1, 7, 8, 4, 8, 6, 8, 9, 9, 9, 0, 2, 0, 6, 0, 3, 1, 7, 1, 2, 1, 4, 2, 0, 3, 2, 7, 4, 3, 4, 7, 9, 4, 5, 6, 6, 8, 2, 4, 7

Offset: 1

Author

Juri-Stepan Gerasimov, Jan 11 2009

Keywords

• nonn
• base
• less

Comments

The digits of A129808 at prime indices.

Crossrefs

Cf. A000040, A154513, A154520.

Programs

Maple

a129808 := [1] : for n from 4 to 400 do if not isprime(n) then a129808 := [op(a129808), op(ListTools[Reverse](convert(n,base,10))) ] ; fi; od:
for n from 1 do p := ithprime(n) ; printf("%d,", op(p,a129808) ) ; od: # R. J. Mathar, Aug 03 2009

Formula

a(n) = A129808(prime(n)) .

Extensions

Edited and corrected by R. J. Mathar, Aug 03 2009