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 A088604 #10 Sep 23 2023 03:39:26 %S A088604 2,13,113,1223,12113,121283,1237547,12184967,124536947,1219861613, %T A088604 12181833347,121339693967,1213536676883,12673876537547, %U A088604 121848768729173,1275463876537547,12429121339693967,165678739293946997 %N A088604 a(n) = smallest prime in which n substrings containing the least significant digit are primes. %C A088604 a(n) need not contain a(n-1) as a substring. %C A088604 We exclude substrings that begin with 0, so a(3) is not 103. - _David Wasserman_, Aug 12 2005 %C A088604 Agrees with A127891 for 24 terms, but A127891 ends there while this sequence continues. - _Ray Chandler_, Mar 13 2007 %e A088604 a(4) = 1223 in which the four substrings containing the LSD (3,23,223,1223) are primes. %o A088604 (PARI) f(n, d, digs, spare) = local(p, r, found); if (!d, return(n)); found = 0; for (i = 0, 9, p = n + i*10^digs; if ((i && isprime(p)) || spare, r = f(p, d - 1, digs + 1, spare - 1 + (i && isprime(p)))); if (r && (r < found || !found), found = r)); found; %o A088604 a(n) = local(i, r); i = 0; while (1, r = f(0, n + i, 0, i); if (r, return(r), i++)); \\ _David Wasserman_, Aug 12 2005 %Y A088604 Cf. A088603, A127891. %K A088604 base,nonn %O A088604 1,1 %A A088604 _Amarnath Murthy_, Oct 15 2003 %E A088604 More terms from _David Wasserman_, Aug 12 2005