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A275451 Number of occurrences of the string n in primorial(n). 1
0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 1, 1, 0, 2, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 3, 0, 0, 3, 2, 2, 1, 1, 1, 1, 2, 0, 5, 4, 4, 2, 4, 4, 0, 0, 4, 2, 4, 3, 1, 0, 1, 0, 1, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,36

LINKS

Table of n, a(n) for n=1..82.

FORMULA

a(A275450(n)) > 0.

EXAMPLE

Primorial(3) equals 30, which contains 3 once, therefore a(3) = 1.

MATHEMATICA

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

Table[Length[StringPosition[ToString[primorial[n]], ToString[n]]], {n, 1, 100}]

SequenceCount[IntegerDigits[#[[1]]], IntegerDigits[#[[2]]]]&/@With[ {nn=90}, Thread[ {FoldList[ Times, Prime[Range[nn]]], Range[nn]}]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Sep 16 2017 *)

CROSSREFS

Cf. A002110 (primorial numbers), A275450.

Sequence in context: A133685 A281492 A112183 * A269317 A119557 A125919

Adjacent sequences:  A275448 A275449 A275450 * A275452 A275453 A275454

KEYWORD

base,easy,nonn

AUTHOR

Ivan N. Ianakiev, Jul 28 2016

STATUS

approved

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Last modified August 9 13:57 EDT 2020. Contains 336323 sequences. (Running on oeis4.)