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A102608 Numbers L such that 1LM1 is prime and M=L+1. 2
2, 4, 11, 22, 25, 26, 28, 31, 32, 40, 44, 47, 52, 58, 70, 73, 79, 80, 86, 88, 89, 92, 1009, 1010, 1013, 1016, 1045, 1051, 1070, 1079, 1081, 1088, 1090, 1097, 1111, 1135, 1139, 1142, 1144, 1154, 1162, 1168, 1178, 1190, 1192, 1213, 1228, 1234, 1280, 1283, 1286 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..51.

EXAMPLE

If L=2, then M=3 and 1231 is prime.

If L=40, then M=41 and 140411 is prime.

If L=88, then M=89 and 188891 is prime.

MATHEMATICA

Select[Range[1300], PrimeQ[FromDigits[Flatten[IntegerDigits /@ {1, #, # + 1, 1}]]] &]

CROSSREFS

Cf. A102606, A102607.

Sequence in context: A152597 A126972 A018774 * A018259 A018480 A004646

Adjacent sequences:  A102605 A102606 A102607 * A102609 A102610 A102611

KEYWORD

nonn,base

AUTHOR

Parthasarathy Nambi, Jan 29 2005

EXTENSIONS

Extended by Ray Chandler, Jan 30 2005

STATUS

approved

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Last modified December 7 05:39 EST 2016. Contains 278841 sequences.