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Search: id:A086151
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| A086151 |
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Number of permutations of decimal digits of 2^n which yield a prime. |
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+0
1
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| 1, 0, 0, 1, 1, 0, 2, 0, 2, 4, 0, 0, 5, 19, 10, 3, 87, 9, 0, 377, 293, 84, 9, 265, 142, 502
(list; graph; listen)
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OFFSET
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1,7
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FORMULA
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a(n)=A039999[A000079(n)]
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EXAMPLE
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n=19: 2^19=524288, has 180 permutations, each composite,a(19)=0;
n=13: 2^13=8192, the following 5 of the 24 permutations provide primes: {8219,8291,1289,9281,2819}.
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MATHEMATICA
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Table[Count[Table[PrimeQ[tn[Part[Permutations[ IntegerDigits[2^w]], j]]], {j, 1, Length[Permutations[ IntegerDigits[2^w]]]}], True], {w, 1, 20}]
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CROSSREFS
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Cf. A039999, A086150, A000079.
Sequence in context: A072514 A071547 A089839 this_sequence A099090 A099040 A136717
Adjacent sequences: A086148 A086149 A086150 this_sequence A086152 A086153 A086154
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KEYWORD
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base,nonn
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AUTHOR
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Labos E. (labos(AT)ana.sote.hu), Aug 04 2003
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