A083786 Composite numbers mod 10.

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

Offset: 1

Author

Roger L. Bagula, Aug 21 2003

Keywords

• nonn
• easy

Links

• G. C. Greubel, Table of n, a(n) for n = 1..5000

Crossrefs

Cf. A002808, A007652.

Programs

Mathematica

Mod[Rest@ Select[Range@140, !PrimeQ@# &], 10] (* Robert G. Wilson v, Mar 17 2006 *)

PARI

lista(nn) = forcomposite(n=2, nn, print1(n % 10, ", ")); \\ Michel Marcus, Oct 30 2017

Formula

a(n) = A002808(n) mod 10. - Ray Chandler, Sep 04 2003

Extensions

More terms from Ray Chandler, Sep 04 2003

Entries checked by Robert G. Wilson v, Mar 17 2006