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A275450 Numbers n such that primorial(n) contains n as a string of digits. 2
3, 9, 21, 27, 34, 35, 36, 37, 38, 39, 41, 42, 43, 44, 45, 46, 50, 51, 52, 53, 56, 57, 58, 59, 60, 61, 62, 63, 65, 66, 67, 68, 69, 70, 73, 74, 75, 76, 77, 79, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 103, 107 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

A275451(a(n)) > 0.

EXAMPLE

Primorial(3) equals 30, which contains 3, therefore 3 is in the sequence.

MAPLE

count:= 0:

P:= 2; p:= 2;

for n from 2 while count < 1000 do

  p:= nextprime(p);

  P:= P*p;

  if StringTools:-Search(sprintf("%d", n), sprintf("%d", P))<>0 then

     count:= count+1;

     A[count]:= n;

  fi

od:

seq(A[i], i=1..count); # Robert Israel, Jul 29 2016

MATHEMATICA

primorial[n_]:=Product[Prime[i], {i, 1, n}];

Select[Range@500, StringContainsQ[ToString[primorial[#]], ToString[#]]&]

PROG

(Perl) use ntheory ":all"; my @a275450 = grep { index(pn_primorial($_), $_) >= 0 } 1 .. 1000; say "@a275450"; # Dana Jacobsen, Aug 09 2016

CROSSREFS

Cf. A002110 (primorial numbers), A275451.

Sequence in context: A127174 A251535 A191177 * A244972 A044055 A029542

Adjacent sequences:  A275447 A275448 A275449 * A275451 A275452 A275453

KEYWORD

base,easy,nonn

AUTHOR

Ivan N. Ianakiev, Jul 28 2016

STATUS

approved

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Last modified October 15 01:40 EDT 2019. Contains 328025 sequences. (Running on oeis4.)