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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. 0
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
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
Sequence in context: A158918 A185885 A212079 * A256746 A086004 A090887
KEYWORD
base,nonn
AUTHOR
Ray Chandler and Ki Punches, Jul 16 2009
STATUS
approved

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Last modified June 13 15:51 EDT 2024. Contains 373389 sequences. (Running on oeis4.)