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A167677
Replace prime digits with 1 and nonprime digits with 2.
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
MATHEMATICA
Table[FromDigits[If[PrimeQ[ # ], 1, 2]&/@IntegerDigits[n]], {n, 0, 200}]
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Zak Seidov, Nov 09 2009
STATUS
approved