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.

1, 3, 7, 11, 13, 29, 37, 113, 121, 149, 151, 201, 219, 251, 451, 453, 573, 669, 689, 697, 749, 913, 969, 1157, 1269, 1503, 1531, 1809, 2087, 2163, 2179, 2511, 2537, 2599, 2709, 2789, 2929, 3243, 3989, 4033, 4151, 5019, 5389, 5423, 5599, 6179, 6433, 8267

Offset

1,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..200 (first 100 terms from Paolo P. Lava)

Mathematica

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 *)
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 *)

Crossrefs

Cf. A033680, A092528, A069602, A074338, A074339, A074340, A074341, A074342, A074343, A074344, A074345, A074346.

Sequence in context: A114273 A173295 A191040 * A086475 A154832 A164568

Adjacent sequences: A074333 A074334 A074335 * A074337 A074338 A074339

Keyword

nonn,base

Author

Zak Seidov, Sep 23 2002

Extensions

More terms from Robert G. Wilson v, Aug 05 2005

Status

approved