A186206 - OEIS

A186206

The first n-digit prime in the decimal expansion of gamma, the Euler-Mascheroni constant.

5, 53, 577, 3359, 64901, 939923, 2402431, 72156649, 215664901, 7215664901, 24310421593, 721566490153, 2359880576723, 42159335939923, 359399235988057, 6749514631447249, 98805767234884867, 402431042159335939

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OFFSET

1,1

COMMENTS

Euler-Mascheroni Gamma = 0.577215664901532860606512090082402431042...

LINKS

Table of n, a(n) for n=1..18.

EXAMPLE

Positions in A001620: 1, 13, 1, 43, 8, 46, 30, 3, 4, 3, 33, 3, 50, 38, 44, 96, 53, 31, 40, 64, ...

MAPLE

Digits := 10000: p0 := evalf(gamma)*10:for d from 1 to 20 do: id:=0:for i from

0 to 50000 while(id=0) do :q0:=trunc(p0*10^(i+d-1)): x:= irem(q0, 10^d): if type(x, prime)=true

and length(x)=d then printf(`%d, `, x):id:=1: else fi:od:od:~

MATHEMATICA

With[{eg=RealDigits[EulerGamma, 10, 250][[1]]}, Table[First[Select[ FromDigits/@Partition[eg, n, 1], PrimeQ[#]&&IntegerLength[#]==n&]], {n, 20}]] (* Harvey P. Dale, Sep 29 2011 *)

CROSSREFS

Cf. A001620.

Sequence in context: A069592 A350995 A065534 * A123788 A333096 A036910

Adjacent sequences: A186203 A186204 A186205 * A186207 A186208 A186209

KEYWORD

nonn,base

AUTHOR

Michel Lagneau, Feb 15 2011

STATUS

approved