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A228123 Number of primes generated from Euler's polynomial x^2 + x + 41 from x = 1 to 10^n. 2
1, 10, 86, 581, 4148, 31984, 261080, 2208196, 19132652, 168806740 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..9.

EXAMPLE

a(4) = 4148 because Number of primes generated from Euler's polynomial x^2 + x + 41 from x = 1 to 10^4 are 4148.

MATHEMATICA

a = 0; n = 1; t = {}; Do[If[PrimeQ[x^2 + x + 41], a = a + 1]; If[Mod[x, n] == 0, n = n*10; AppendTo[t, a]], {x, 1, 1000000000}]; t

CROSSREFS

Cf. A005846, A056561.

Sequence in context: A145146 A252981 A184122 * A163412 A287827 A321853

Adjacent sequences:  A228120 A228121 A228122 * A228124 A228125 A228126

KEYWORD

nonn

AUTHOR

Shyam Sunder Gupta, Aug 11 2013

STATUS

approved

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Last modified October 22 04:25 EDT 2019. Contains 328315 sequences. (Running on oeis4.)