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 A104304 #12 Jul 15 2025 08:26:55 %S A104304 1876918496182251795617689,3648136100357213534434969, %T A104304 297025295936294849293764292681,466489465124463761462400461041, %U A104304 16770251674436167184916692641666681,17556251752976175032917476841745041,30660013062500305900130555043052009,31506253147076314352931399843136441 %N A104304 Primes which are the reverse concatenation of five consecutive square numbers. %H A104304 Amiram Eldar, <a href="/A104304/b104304.txt">Table of n, a(n) for n = 1..10000</a> %e A104304 The first term is 1876918496182251795617689 which is a prime and is the reverse concatenation of 17689, 17956, 18225, 18496 and 18769 which are five consecutive square numbers. %t A104304 cat[s_] := FromDigits[Flatten[IntegerDigits[s]]]; Select[cat /@ Reverse /@ Partition[Range[3000]^2, 5, 1], PrimeQ] (* _Amiram Eldar_, Jul 15 2025 *) %Y A104304 Cf. A104301, A104302, A104303. %K A104304 base,nonn %O A104304 1,1 %A A104304 _Shyam Sunder Gupta_, Apr 17 2005 %E A104304 More terms from _Amiram Eldar_, Jul 15 2025