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A092002
Numbers that can be expressed as the difference of the squares of primes in exactly six distinct ways.
0
840, 1320, 1680, 2520, 3192, 3432, 4920, 5208, 5280, 5712, 6552, 6888, 9360, 11928, 16008, 19152, 19992, 25200, 29568, 31080, 35880, 38280, 38640, 40920, 41832, 45240, 47880, 48360, 48720, 51240, 51480, 53040, 56280, 57288, 61320, 63240
OFFSET
1,1
EXAMPLE
840 = 31^2-11^2 = 37^2-23^2 = 41^2-29^2 = 47^2-37^2 = 73^2-67^2 =
107^2-103^2
MATHEMATICA
Take[Transpose[Select[Tally[Sort[Last[#]-First[#]&/@(Subsets[ Prime[ Range[ 2000]], {2}]^2)]], Last[#]==6&]][[1]], 40] (* Harvey P. Dale, Nov 17 2013 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Ray Chandler, Feb 22 2004
STATUS
approved