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A250298
Primes p such that the largest integer m such that both m and m-1 factor into primes less than or equal to p is a perfect square, m = k^2.
1
3, 5, 11, 13, 29, 53, 103
OFFSET
1,1
COMMENTS
List of primes p = A000040(i) such that A117581(i) (that is, A002072(i)+1) is a perfect square.
There are no analogous primes p < 107 for which m-1 defined above is a perfect square.
EXAMPLE
p = 3 gives m = 3^2;
p = 5 gives m = 9^2;
p = 11 gives m = 99^2;
p = 13 gives m = 351^2;
p = 29 gives m = 13311^2;
p = 53 gives m = 1205645^2;
p = 103 gives m = 138982582999^2.
CROSSREFS
KEYWORD
hard,more,nonn
AUTHOR
Don N. Page, Jan 15 2015
STATUS
approved