A033681 -id:A033681 - cp's OEIS frontend

A046259 a(1) = 9; a(n) is smallest number >= a(n-1) such that the juxtaposition a(1)a(2)...a(n) is a prime.

9, 11, 21, 21, 23, 33, 37, 93, 119, 129, 133, 147, 293, 321, 429, 433, 497, 627, 661, 897, 1161, 1187, 1197, 1711, 1769, 1807, 2097, 2099, 4143, 4149, 4197, 4587, 4587, 5629, 5711, 5889, 6153, 6351, 6399, 6511, 6651, 7179, 7563, 7661, 8071, 8163, 9663

Offset: 1

Patrick De Geest, May 15 1998

nonn

Cf. A069611, A074345, A033680, A033679, A033681, A046254, A046255, A046256, A046257, A046258, A111524.

a[1] = 9; a[n_] := a[n] = Block[{k = a[n - 1], 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, Aug 05 2005 *)

A074339 a(1) = 3; a(n) is smallest number > a(n-1) such that the juxtaposition a(1)a(2)...a(n) is a prime.

Original entry on oeis.org

3, 7, 9, 51, 57, 103, 119, 121, 183, 293, 301, 351, 447, 479, 577, 741, 839, 1051, 1277, 1431, 1633, 1877, 2043, 2251, 2303, 2659, 2937, 3447, 3897, 3969, 4059, 4179, 4371, 4389, 4563, 4841, 4903, 5097, 5103, 5369, 5689, 6621, 6831, 6927, 7479, 9227, 9351

Offset: 1

Zak Seidov, Sep 23 2002

Cf. A069605, A033681, A074336, A074338, A074340, A074341, A074342, A074343, A074344, A074345, A074346.

a[1] = 3; 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, 47}] (* Robert G. Wilson v *)

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

cp's OEIS Frontend

A046259 a(1) = 9; a(n) is smallest number >= a(n-1) such that the juxtaposition a(1)a(2)...a(n) is a prime.

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