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A145292
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Composite numbers generated by the Euler polynomial x^2 + x + 41.
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7
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1681, 1763, 2021, 2491, 3233, 4331, 5893, 6683, 6847, 7181, 7697, 8051, 8413, 9353, 10547, 10961, 12031, 13847, 14803, 15047, 15293, 16043, 16297, 17071, 18673, 19223, 19781, 20633, 21797, 24221, 25481, 26123, 26447, 26773, 27101, 29111
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| Euler polynomial is giving primes for consecutive x from 0 to 39. Numbers x for which x^2 + x + 41 is not prime see A007634.
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LINKS
| Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
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FORMULA
| a(n) ~ n^2. [Charles R Greathouse IV, Dec 08 2011]
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MATHEMATICA
| a = {}; Do[If[PrimeQ[x^2 + x + 41], null, AppendTo[a, x^2 + x + 41]], {x, 0, 500}]; a
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PROG
| (Haskell)
a145292 n = a145292_list !! (n-1)
a145292_list = filter ((== 0) . a010051) a202018_list
-- Reinhard Zumkeller, Dec 09 2011
(PARI) for(n=1, 1e3, if(!isprime(t=n^2+n+41), print1(t", "))) \\ Charles R Greathouse IV, Dec 08 2011
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CROSSREFS
| Cf. A005846, A007634, A145293, A145294, A145295.
Intersection of A002808 and A202018; A010051.
Sequence in context: A172673 A172768 A172667 * A175897 A189654 A163009
Adjacent sequences: A145289 A145290 A145291 * A145293 A145294 A145295
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KEYWORD
| nonn
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AUTHOR
| Artur Jasinski (grafix(AT)csl.pl), Oct 06 2008
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