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 A379426 #4 Dec 23 2024 01:56:11
%S A379426 2,23,2357,23581,2358247,235824913,235824916247,
%T A379426 2358249162515829584909,
%U A379426 235824916251582958491829824917162558516292249258249589629182571583855789,2358249162515829584918298249171625585162922492582495896291825715838558298516316558918298250261
%N A379426 Prime terms in A287353.
%C A379426 Primes Sum_{i=1..k} 10^(k-i)*prime(i) for some k.
%e A379426 k prime(k) A287353(k) n a(n)
%e A379426 --- -------- ---------- --- -------
%e A379426 1 2 2 1 2
%e A379426 2 3 23 2 23
%e A379426 3 5 235
%e A379426 4 7 2357 3 2357
%e A379426 5 11 23581 4 23581
%e A379426 6 13 235823
%e A379426 7 17 2358247 5 2358247
%o A379426 (Python)
%o A379426 from sympy import isprime, nextprime
%o A379426 m = p = 0
%o A379426 while p < 500:
%o A379426 p = nextprime(p); m = 10*m + p
%o A379426 if isprime(m): print(m, end = ', ')
%Y A379426 Cf. A013918, A069151, A287353.
%K A379426 nonn
%O A379426 1,1
%A A379426 _Ya-Ping Lu_, Dec 22 2024