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A064779 Primes such that the sum of their digits and the sum of the reciprocals of their digits is also prime. 0
11, 2441, 4241, 4421, 12163, 12613, 13313, 13331, 16231, 16363, 16633, 21163, 21613, 26113, 31663, 32233, 32323, 32611, 33113, 33223, 33311, 48281, 48821, 61231, 61363, 62131, 62311, 63211, 63361, 88241 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

MATHEMATICA

f[ n_ ] := 1/n a[ n_ ] := Apply[ Plus, Map[ f, IntegerDigits[ n ] ] ] b[ n_ ] := Apply[ Plus, IntegerDigits[ n ] ] Select[ Range[ 100000 ], FreeQ[ IntegerDigits[ # ], 0 ] && PrimeQ[ a[ # ] ] && PrimeQ[ b[ # ] ] && PrimeQ[ # ] & ]

CROSSREFS

Cf. A034708.

Sequence in context: A078271 A087403 A085878 * A138075 A185556 A134806

Adjacent sequences:  A064776 A064777 A064778 * A064780 A064781 A064782

KEYWORD

base,nonn

AUTHOR

Santi Spadaro (spados(AT)katamail.com), Oct 19 2001

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Last modified February 16 13:02 EST 2012. Contains 205909 sequences.