A167678 Replace prime digits with 2 and nonprime digits with 1.

1, 1, 2, 2, 1, 2, 1, 2, 1, 1, 11, 11, 12, 12, 11, 12, 11, 12, 11, 11, 21, 21, 22, 22, 21, 22, 21, 22, 21, 21, 21, 21, 22, 22, 21, 22, 21, 22, 21, 21, 11, 11, 12, 12, 11, 12, 11, 12, 11, 11, 21, 21, 22, 22, 21, 22, 21, 22, 21, 21, 11, 11, 12, 12, 11, 12, 11, 12, 11, 11, 21, 21, 22

Offset

0,3

Links

Table of n, a(n) for n=0..72.

Mathematica

Table[FromDigits[If[PrimeQ[ # ], 2, 1]&/@IntegerDigits[n]], {n, 0, 200}]

Crossrefs

Cf. A065031, A167677, A167679.

Sequence in context: A323826 A275824 A324869 * A078614 A026607 A319981

Adjacent sequences: A167675 A167676 A167677 * A167679 A167680 A167681

Keyword

base,nonn

Author

Zak Seidov, Nov 09 2009

Status

approved