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 A074336 #22 Sep 10 2024 19:41:55
%S A074336 1,3,7,11,13,29,37,113,121,149,151,201,219,251,451,453,573,669,689,
%T A074336 697,749,913,969,1157,1269,1503,1531,1809,2087,2163,2179,2511,2537,
%U A074336 2599,2709,2789,2929,3243,3989,4033,4151,5019,5389,5423,5599,6179,6433,8267
%N A074336 a(1) = 1; a(n) is smallest number > a(n-1) such that the juxtaposition a(1)a(2)...a(n) is a prime.
%H A074336 Vincenzo Librandi, <a href="/A074336/b074336.txt">Table of n, a(n) for n = 1..200</a> (first 100 terms from Paolo P. Lava)
%t A074336 a[1] = 1; a[n_] := a[n] = Block[{k = a[n - 1] + 1 + Mod[a[n - 1], 2], c = IntegerDigits @ Table[ a[i], {i, n - 1}]}, While[ !PrimeQ[ FromDigits @ Flatten @ Append[c, IntegerDigits[k]]], k += 2]; k]; Table[ a[n], {n, 48}] (* _Robert G. Wilson v_ *)
%t A074336 nxt[{j_,a_}]:=Module[{k=a+1},While[!PrimeQ[j*10^IntegerLength[k]+k],k++];{j*10^ IntegerLength[ k]+k,k}]; NestList[nxt,{1,1},50][[;;,2]] (* _Harvey P. Dale_, Sep 10 2024 *)
%Y A074336 Cf. A033680, A092528, A069602, A074338, A074339, A074340, A074341, A074342, A074343, A074344, A074345, A074346.
%K A074336 nonn,base
%O A074336 1,2
%A A074336 _Zak Seidov_, Sep 23 2002
%E A074336 More terms from _Robert G. Wilson v_, Aug 05 2005