A162895 - OEIS

The OEIS is supported by the many generous donors to the OEIS Foundation.

A162895

Integers n such that the century defined by the interval [100n+1, 100n+100] (i.e., the (n+1)-st century) contains exactly one Ormiston prime pair and no other primes.

12907, 18270, 21569, 32666, 37606, 52126, 54347, 61411, 62674, 71369, 71862, 75799, 85596, 87991, 91134, 96842, 101269, 106456, 109524, 109557, 113663, 117385, 128411, 129762, 137489, 140643, 150808, 153329, 158982, 161505, 163740

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Table of n, a(n) for n=1..31.

EXAMPLE

12907 is included since (1290719,1290791) is an Ormiston prime pair and there are no other primes in the century.

MATHEMATICA

oppQ[n_]:=Module[{r1=100n+1, r2=100n+100, prs}, prs=Select[Range[r1, r2], PrimeQ]; Length[prs] == 2&&Sort[IntegerDigits[prs[[1]]]]==Sort[IntegerDigits[prs[[2]]]]]; Select[Range[170000], oppQ] (* Harvey P. Dale, Jul 18 2023 *)

CROSSREFS

Cf. A162893, A162894.

Sequence in context: A158918 A185885 A212079 * A256746 A086004 A090887

Adjacent sequences: A162892 A162893 A162894 * A162896 A162897 A162898

KEYWORD

base,nonn

AUTHOR

Ray Chandler and Ki Punches, Jul 16 2009

STATUS

approved