A180949 - OEIS

A180949

Prime numbers P such that 10^(n+d+1) + P*10^n + 1 is prime for n=1 to 5 with d = number of digits of P.

223283, 248903, 924773, 1469627, 2121767, 2428241, 2429411, 2614043, 2885453, 3444893, 3512849, 3564461, 4316141, 4438067, 4605977, 4980161, 5267519, 6248057, 6961673, 7519607, 8517563, 9716789, 9846443, 12383099, 13127507

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OFFSET

1,1

COMMENTS

For P = 6961673,9846443,17990729,28587371 Q is prime for n=1 to 6

For P = 5267519,27060587 Q is prime for n=1 to 7

LINKS

Table of n, a(n) for n=1..25.

EXAMPLE

5267519

1052675191

10526751901

105267519001

1052675190001

10526751900001

105267519000001

1052675190000001

are all prime numbers

CROSSREFS

Sequence in context: A258907 A253739 A274809 * A165411 A235909 A233966

Adjacent sequences: A180946 A180947 A180948 * A180950 A180951 A180952

KEYWORD

nonn,base

AUTHOR

Pierre CAMI, Sep 27 2010

STATUS

approved