This site is supported by donations to The OEIS Foundation.

Thanks to everyone who made a donation during our annual appeal!
To see the list of donors, or make a donation, see the OEIS Foundation home page.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A086151 Number of permutations of decimal digits of 2^n which yield a prime. 0
 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; refs; listen; history; text; internal format)
 OFFSET 1,7 LINKS FORMULA a(n)=A039999[A000079(n)] EXAMPLE 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}. MATHEMATICA Table[Count[Table[PrimeQ[tn[Part[Permutations[ IntegerDigits[2^w]], j]]], {j, 1, Length[Permutations[ IntegerDigits[2^w]]]}], True], {w, 1, 20}] CROSSREFS Cf. A039999, A086150, A000079. Sequence in context: A089839 A206823 A151668 * A099040 A185296 A136717 Adjacent sequences:  A086148 A086149 A086150 * A086152 A086153 A086154 KEYWORD base,nonn AUTHOR Labos Elemer, Aug 04 2003 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified January 19 16:32 EST 2019. Contains 319309 sequences. (Running on oeis4.)