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A086150 Number of permutations of decimal digits of n which yield nonprime numbers. 2
1, 0, 0, 1, 0, 1, 0, 1, 1, 2, 0, 2, 0, 1, 2, 1, 0, 2, 1, 1, 2, 1, 1, 2, 2, 2, 2, 2, 1, 1, 0, 1, 1, 1, 1, 2, 0, 1, 2, 2, 1, 2, 1, 1, 2, 2, 1, 2, 2, 1, 2, 2, 1, 2, 1, 2, 2, 2, 1, 2, 1, 2, 2, 2, 2, 1, 1, 2, 2, 1, 0, 2, 0, 1, 2, 1, 1, 2, 0, 2, 2, 2, 1, 2, 2, 2, 2, 1, 1, 2, 1, 1, 2, 2, 1, 2, 0, 1, 1, 3, 1, 6, 3, 4, 6 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,10

COMMENTS

From Robert Israel, Aug 13 2017: (Start)

Leading zeros are allowed.

a(n) = 0 for n in A003459. (End)

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

FORMULA

a(n) + A039999(n) = A047726(n). - Robert Israel, Aug 13 2017

EXAMPLE

n=117, digit-permutations={117,171,711} are all composites, so a(117)=3.

MAPLE

f:= proc(L) option remember;

  nops(remove(isprime, map(t -> add(t[i]*10^(i-1), i=1..nops(t)), combinat:-permute(L))))

end proc:

seq(f(sort(convert(n, base, 10))), n=1..200); # Robert Israel, Aug 13 2017

MATHEMATICA

nd[x_, y_] := 10*x+y tn[x_] := Fold[nd, 0, x] Table[Count[Table[PrimeQ[tn[Part[Permutations[ IntegerDigits[w]], j]]], {j, 1, Length[Permutations[ IntegerDigits[w]]]}], False], {w, 1, 128}]

Table[Count[FromDigits/@Permutations[IntegerDigits[n]], _?(!PrimeQ[#]&)], {n, 110}] (* Harvey P. Dale, Dec 24 2016 *)

CROSSREFS

Cf. A003459, A039999, A047726.

Sequence in context: A218907 A192575 A029401 * A105166 A321299 A105783

Adjacent sequences:  A086147 A086148 A086149 * A086151 A086152 A086153

KEYWORD

base,nonn

AUTHOR

Labos Elemer, Aug 04 2003

STATUS

approved

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Last modified September 21 19:59 EDT 2019. Contains 327282 sequences. (Running on oeis4.)