A167677 Replace prime digits with 1 and nonprime digits with 2.

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

Offset

0,1

Links

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

Mathematica

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

Crossrefs

Cf. A065031, A167678, A167679.

Sequence in context: A276729 A257629 A143331 * A278387 A351617 A074293

Adjacent sequences: A167674 A167675 A167676 * A167678 A167679 A167680

Keyword

base,nonn

Author

Zak Seidov, Nov 09 2009

Status

approved