A083993 a(1) = 3; a(n) = smallest number such that the forward as well as the reverse n-th partial concatenation is a prime for n>1. (Reverse concatenation is taken term-wise and not digit-wise).

3, 1, 1, 39, 87, 57, 171, 129, 219, 399, 459, 1719, 719, 61, 5811, 383, 1519, 23889, 1001, 3133, 4491, 4767, 519, 4253, 111, 34251, 12303, 5143, 16943, 19293, 361, 21771, 18803, 2919, 44787, 66819, 42897, 21541, 15299, 21387, 11613, 29133, 16839

Offset

0,1

Links

Table of n, a(n) for n=0..42.

Crossrefs

Cf. A083992, A083994.

Sequence in context: A126465 A077509 A156698 * A156727 A173505 A253178

Adjacent sequences: A083990 A083991 A083992 * A083994 A083995 A083996

Keyword

base,nonn

Author

Amarnath Murthy, May 23 2003

Extensions

Corrected and extended by Ray Chandler, Aug 03 2003

Status

approved