A104938 Primes from merging of 4 successive digits in decimal expansion of the Euler-Mascheroni constant A001620.

3359, 3593, 5939, 9923, 8677, 2677, 6709, 6947, 6329, 2917, 4951, 1447, 4283, 2417, 6449, 5003, 3733, 3767, 7673, 9491, 2039, 5323, 6211, 4793, 7937, 7057, 3547, 6043, 6733, 7331, 3313, 1399, 7541, 5413, 4139, 8423, 4877, 8431, 3109, 1093, 9973, 3613

Offset: 1

Author

Andrew G. West (WestA(AT)wlu.edu), Mar 29 2005

Keywords

• nonn
• base

Comments

Leading zeros are not permitted, so each term is 4 digits in length.

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..1000
• Jon Borwein, 170,000 digits of Gamma [Wayback Machine copy]
• Eric Weisstein's World of Mathematics, Euler-Mascheroni Constant.

Crossrefs

Cf. A198778.

Cf. A103773, A103789, A103793, A103808 - A103812, A104824- A104826, A104843 - A104850, A198161 - A198177, A198776 - A198784. - Harvey P. Dale, Oct 29 2011

Programs

Maple

Digits := 420 ;
for sh from 3 do
        p := floor(gamma*10^sh) mod 10000 ;
        if isprime(p) and p > 999 then
                printf("%d,",p);
        end if;
end do: # R. J. Mathar, Oct 31 2011

Mathematica

egp[len_]:=Module[{egterms=FromDigits/@Partition[RealDigits[EulerGamma, 10, 1000][[1]],len,1]},Select[egterms,IntegerLength[#]==len&&PrimeQ[#]&]]; egp[4] (* Harvey P. Dale, Oct 29 2011 *)

PARI

L=10^4;for(i=3,999,isprime(p=Euler\.1^i%L)&p*10>L&print1(p",")) \\ M. F. Hasler, Oct 31 2011

Extensions

Offset changed from 0 to 1 by Vincenzo Librandi, Apr 21 2013