A102607 Numbers L such that 1LMN1 is prime, where M=L+1 and N=M+1.

3, 4, 5, 7, 12, 17, 24, 28, 33, 35, 37, 39, 40, 41, 50, 55, 58, 62, 66, 67, 75, 77, 79, 80, 90, 91, 97, 104, 109, 116, 125, 137, 141, 160, 174, 176, 186, 189, 195, 207, 211, 223, 227, 236, 241, 245, 257, 273, 277, 279, 288, 290, 297, 300, 304, 305, 313, 314, 333, 336

Offset

1,1

Links

Table of n, a(n) for n=1..60.

Example

If L=3, then M=4 and N=5 and 13451 is prime.
If L=35, then M=36 and N=37 and 13536371 is prime.
If L=67, then M=68 and N=69 and 16768691 is prime.

Mathematica

Select[Range[340], PrimeQ[FromDigits[Flatten[IntegerDigits /@ {1, #, # + 1, # + 2, 1}]]] &]

Crossrefs

Cf. A102606, A102608.

Sequence in context: A173444 A120424 A139440 * A360688 A079463 A325422

Adjacent sequences: A102604 A102605 A102606 * A102608 A102609 A102610

Keyword

nonn,base

Author

Parthasarathy Nambi, Jan 29 2005

Extensions

Extended by Ray Chandler, Jan 30 2005

Status

approved