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A061264
Number of cyclic permutations of the digits of n which give primes.
2
0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 2, 0, 2, 1, 0, 1, 2, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 2, 1, 0, 1, 1, 0, 2, 1, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 2, 0, 2, 1, 0, 1, 0, 0, 2, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 2, 1, 0, 0, 2, 0, 2, 1, 0
OFFSET
1,11
LINKS
EXAMPLE
a(157) = 2 as among the three cyclic permutations 157, 571, 715, two are primes.
MAPLE
A055642 := proc(n) max(1, ilog10(n)+1) ; end: A061264 := proc(n) local ncyc, s, dgs, a, L, i ; a := 0 ; dgs := convert(n, base, 10) ; ncyc := n ; for s from 1 to A055642(n) do if isprime(ncyc) then a := a+1 ; fi; L := ListTools[Rotate](dgs, s) ; ncyc := add(op(i, L)*10^(i-1), i=1..nops(L)) ; od: RETURN(a) ; end: for n from 1 to 120 do printf("%d, ", A061264(n)) ; od: # R. J. Mathar, Oct 02 2008
CROSSREFS
Cf. A039999.
Cf. A046810. - R. J. Mathar, Oct 02 2008
Sequence in context: A083054 A336921 A297742 * A193680 A186809 A112300
KEYWORD
nonn,base
AUTHOR
Amarnath Murthy, Apr 24 2001
EXTENSIONS
More terms from R. J. Mathar, Oct 02 2008
Offset corrected, Joerg Arndt, Aug 05 2015
STATUS
approved