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Search: id:A145694
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| A145694 |
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Numbers Y such that 57*Y^2+19 is a square |
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+0
1
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| 5, 1515, 457525, 138171035, 41727195045, 12601474732555, 3805603642036565, 1149279698420310075, 347078663319291606085, 104816607042727644727595
(list; graph; listen)
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OFFSET
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1,1
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FORMULA
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a(n+2)=302*a(n+1)-a(n)
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EXAMPLE
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a(1)=5 because the first relation is 38^2=57*5^2+19
a(n)=(5/2)*{[151+20*sqrt(57)]^n+[151-20*sqrt(57)]^n}-(1/3)*sqrt(57)*{[151-20*sqrt(57)]^n -[151+20*sqrt(57)]^n}, with n>=0 [From Paolo P. Lava (ppl(AT)spl.at), Nov 25 2008]
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CROSSREFS
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A145120
Sequence in context: A066162 A096725 A062598 this_sequence A014377 A165628 A119747
Adjacent sequences: A145691 A145692 A145693 this_sequence A145695 A145696 A145697
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KEYWORD
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easy,nonn
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AUTHOR
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Richard Choulet (richardchoulet(AT)yahoo.fr), Oct 16 2008
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