This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A072952 #35 Jul 17 2025 08:18:24
%S A072952 5,577,5772156649015328606065120900824024310421
%N A072952 Primes obtained as initial segments of the decimal expansion of the Euler-Mascheroni constant gamma = 0.5772... .
%C A072952 The next term (a(4)) has 185 digits and is too large to include. - _Harvey P. Dale_, May 14 2013
%C A072952 Sequence A065815 gives the number of digits of a(n), resp. numbers k such that a(n) = floor(gamma*10^k). Sequences A005042, A007512, A115453, A119343, A210704, ... are the analog of the present sequence for Pi, e, sqrt(2), sqrt(3), 3^(1/3), ... - _M. F. Hasler_, Aug 31 2013
%C A072952 The original wording of the definition (and example) was "primes found in the decimal expansion..." which could as well refer to the sequence (5,7,7,215664901,5,3,2, ...) or (5,7,72156649, ...) or (5,7,7215664901, ...) (analogs to A047777 or A195834), or to the sequence (5,7,57, ...), analog to A198018. - _M. F. Hasler_, Sep 01 2013
%H A072952 Amiram Eldar, <a href="/A072952/b072952.txt">Table of n, a(n) for n = 1..4</a>
%H A072952 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/ConstantPrimes.html">Constant Primes</a>.
%H A072952 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Euler-MascheroniConstantDigits.html">Euler-Mascheroni Constant Digits</a>.
%H A072952 <a href="/index/Con#constant_primes">Index entries related to "constant primes"</a>.
%e A072952 a(2) = 577, since 577 is the second prime obtained as initial segment of the decimal expansion of Euler-Mascheroni constant gamma = 0.577215664... .
%t A072952 nn=200;With[{emc=RealDigits[EulerGamma,10,nn][[1]]},Select[Table[ FromDigits[ Take[emc,n]],{n,nn}],PrimeQ]] (* _Harvey P. Dale_, May 14 2013 *)
%o A072952 (PARI) default(realprecision, 777); /* use that many digits */
%o A072952 A072952={(c=Euler, v=1/*set to 0 for indices (i.e., A065815) instead of values*/)->for(k=0, precision(c), ispseudoprime(p=c\.1^k)&&print1([k, p][1+v]", "))} \\ _M. F. Hasler_, Aug 31 2013
%Y A072952 Cf. A001620, A047777, A065815, A195834, A198018.
%Y A072952 Analogous sequences: A005042 (Pi), A007512 (e), A115453 (sqrt(2)), A119343 (sqrt(3)), A210704 (3^(1/3)).
%K A072952 nonn,base
%O A072952 1,1
%A A072952 _Shyam Sunder Gupta_, Aug 12 2002