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 A174409 #12 Sep 08 2022 08:45:51 %S A174409 2,107,137,167,257,269,311,317,557,593,761,773,809,911,1103,1151,1283, %T A174409 1289,1481,1487,1559,1709,1787,1931,2111,2141,2243,2339,2357,2657, %U A174409 2687,2777,2909,3137,3209,3251,3359,3371,3389,3449 %N A174409 Prime numbers p such that the concatenation p^3//1331 is a prime number. %C A174409 See comments at A174213. %C A174409 p^3//1331 is the concatenation of the cubes of two primes. %C A174409 With the exception of a(1)=2, each term is necessarily of the form 6*k-1. %H A174409 Harvey P. Dale, <a href="/A174409/b174409.txt">Table of n, a(n) for n = 1..1000</a> %e A174409 The first prime is 2; 2^3 = 8, and 81331 = prime(7958), so a(1)=2. %e A174409 The smallest prime p > 2 such that p^3//1331 yields a prime is p=107: 107^3 = 1225043, and 12250431331 = prime(552342812), so a(2)=107. %t A174409 Select[Prime[Range[500]],PrimeQ[10000#^3+1331]&] (* _Harvey P. Dale_, May 30 2017 *) %o A174409 (Magma) [p: p in PrimesUpTo(5000) | IsPrime(Seqint(Intseq(1331) cat Intseq(p^3)))]; // _Vincenzo Librandi_, Mar 05 2018 %Y A174409 Cf. A168327, A168417, A173836, A174213, A174260, A174229, A174355. %K A174409 base,nonn %O A174409 1,1 %A A174409 Eva-Maria Zschorn (e-m.zschorn(AT)zaschendorf.km3.de), Mar 19 2010