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A225647 Numbers n such that there are no primes in the open interval from (n^2-1)*sqrt(n^2+1) to (n^2+1)*sqrt(n^2-1). 0
1, 3, 4, 6, 7 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Sequence is probably complete. a(6), if it exists, is greater than 4 * 10^18. - Charles R Greathouse IV, May 14 2013

LINKS

Table of n, a(n) for n=1..5.

PROG

(PARI) is(n)=n==1 || nextprime(sqrtint((n^2+1)*(n^2-1)^2-1)+1) > sqrtint((n^2-1)*(n^2+1)^2-1) \\ Charles R Greathouse IV, May 14 2013

CROSSREFS

Sequence in context: A117986 A248738 A070737 * A135599 A283740 A167161

Adjacent sequences:  A225644 A225645 A225646 * A225648 A225649 A225650

KEYWORD

nonn

AUTHOR

Gerasimov Sergey, May 11 2013

STATUS

approved

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Last modified July 18 06:19 EDT 2019. Contains 325134 sequences. (Running on oeis4.)