A083472 Smallest prime p such that the backward concatenation of n consecutive decreasing primes starting with p is a prime.

2, 5, 29, 59, 37, 17, 193, 59, 167, 149, 103, 563, 109, 107, 149, 317, 409, 829, 283, 263, 467, 107, 89, 3181, 313, 113, 431, 521, 739, 577, 487, 617, 1601, 937, 167, 991, 2699, 293, 1481, 3593, 4943, 593, 541, 673, 241, 719, 1217, 449, 421, 1667, 337, 353, 1297

Offset

1,1

Links

Table of n, a(n) for n=1..53.

Example

a(3) = 29 as the concatenation of 29,23 and 19, i.e. 292319, is a prime.

Mathematica

bcpQ[n_]:=PrimeQ[FromDigits[Flatten[IntegerDigits/@Reverse[n]]]]; With[{prs = Prime[ Range[10000]]}, Table[Select[Partition[prs, n, 1], bcpQ, 1][[1, -1]], {n, 60}]] (* Harvey P. Dale, Aug 12 2013 *)

Crossrefs

Cf. A083471.

Sequence in context: A061351 A126107 A193901 * A213996 A057794 A357199

Adjacent sequences: A083469 A083470 A083471 * A083473 A083474 A083475

Keyword

base,nonn

Author

Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 02 2003

Extensions

More terms from David Wasserman, Nov 15 2004

Status

approved