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A144709 Values of n > 2 such that there is not a pair of primes (n^2+n+k, n^2+n-k), 1 <= k < n, between successive squares n^2 and (n+1)^2. 0
17, 19, 46, 58, 64, 67, 85, 367 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

For n = 2,3,4, for example, we have prime pairs (5,7), (11,13), (17,23). Conjecture: the intervals (n^2,[n+1]^2) that do not contain at least one such pair are sparse as n gets large.

LINKS

Table of n, a(n) for n=1..8.

Twin primes

PROG

(PARI) isok(n) = {for (k=1, n-1, if (isprime(n^2+n+k) && isprime(n^2+n-k), return (0)); ); return (1); } \\ Michel Marcus, Aug 31 2013

CROSSREFS

Sequence in context: A108024 A095081 A243437 * A132239 A075432 A232882

Adjacent sequences:  A144706 A144707 A144708 * A144710 A144711 A144712

KEYWORD

nonn,more

AUTHOR

Daniel Tisdale, Sep 19 2008

STATUS

approved

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Last modified June 25 11:31 EDT 2017. Contains 288709 sequences.