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A156345
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Nonprimes with the same number of even digits and prime digits.
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0
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0, 1, 9, 10, 12, 20, 21, 22, 34, 36, 38, 45, 54, 56, 58, 63, 65, 74, 76, 78, 85, 87, 90, 91, 92, 99, 100, 102, 110, 111, 112, 119, 120, 121, 122, 129, 134, 136, 138, 143, 145, 147, 154, 156, 158, 165, 174, 176, 178, 183, 185, 187, 190, 192, 200, 201, 202, 209, 210
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,3
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COMMENTS
| Even digits are 2, 4, 6 or 8. Prime digits are 2, 3, 5 or 7.
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EXAMPLE
| 0(number=0), 1(number=0), 9(number=0), 10(number=0), 12(number=1), 20(number=1), 21(number=1), 22(number=2), 34(number=1), etc.
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MATHEMATICA
| okQ[n_]:=Module[{idn=IntegerDigits[n]}, !PrimeQ[n] && Count[idn, _?PrimeQ] == Count[idn, _?EvenQ]-Count[idn, 0]]; Select[Range[0, 250], okQ] (* From Harvey P. Dale, Jan 12 2012 *)
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CROSSREFS
| Cf. A141468.
Sequence in context: A160947 A158581 A078459 * A078390 A037408 A178680
Adjacent sequences: A156342 A156343 A156344 * A156346 A156347 A156348
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KEYWORD
| nonn,base,less
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AUTHOR
| Juri-Stepan Gerasimov (2stepan(AT)rambler.ru), Feb 08 2009
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EXTENSIONS
| Removed 69, inserted 99 and 209 . R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Feb 13 2009
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