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A258841 a(n) = 9*n^2 - 237*n + 1927. 0
1927, 1699, 1489, 1297, 1123, 967, 829, 709, 607, 523, 457, 409, 379, 367, 373, 397, 439, 499, 577, 673, 787, 919, 1069, 1237, 1423, 1627, 1849, 2089, 2347, 2623, 2917, 3229, 3559, 3907, 4273, 4657, 5059, 5479, 5917, 6373, 6847, 7339, 7849, 8377, 8923, 9487, 10069 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Empirical observation. All integers generated by polynomial for 0 < n <= 37 are prime with the exception of a(26) = 43^2 and a(29) = 43*61.

LINKS

Table of n, a(n) for n=0..46.

Eric Weisstein's World of Mathematics, Prime-Generating Polynomial

Index entries for linear recurrences with constant coefficients, signature (3,-3,1).

FORMULA

G.f.: (1927 - 4082*x + 2173*x^2)/(1-x)^3. - Vincenzo Librandi, Jun 22 2015

a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3). - Vincenzo Librandi, Jun 22 2015

MATHEMATICA

Table[9 n^2 - 237 n + 1927, {n, 0, 25}] (* Michael De Vlieger, Jun 12 2015 *)

PROG

(PARI) vector(50, n, 9*n^2 - 237*n + 1927) \\ Michel Marcus, Jun 21 2015

(MAGMA) [9*n^2-237*n+1927: n in [0..50]]; // Vincenzo Librandi, Jun 22 2015

CROSSREFS

Cf. A202018, A214732, A215814.

Sequence in context: A202051 A283949 A133301 * A099482 A253337 A200435

Adjacent sequences:  A258838 A258839 A258840 * A258842 A258843 A258844

KEYWORD

nonn,easy

AUTHOR

Robert Potter, Jun 12 2015

STATUS

approved

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Last modified April 20 22:22 EDT 2019. Contains 322310 sequences. (Running on oeis4.)