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A061264
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Number of cyclic permutations of the digits of n which give primes.
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1
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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
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,11
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EXAMPLE
| a(157) = 2 as among the three cyclic permutations 157, 571, 715, two are primes.
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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: [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Oct 02 2008]
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CROSSREFS
| A039999.
Cf. A046810. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Oct 02 2008]
Sequence in context: A118682 A198393 A083054 * A193680 A186809 A112300
Adjacent sequences: A061261 A061262 A061263 * A061265 A061266 A061267
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KEYWORD
| nonn,base
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AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Apr 24 2001
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EXTENSIONS
| More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Oct 02 2008
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