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A211775 a(n) = 2*n^2 - 212*n + 5419. 2
5419, 5209, 5003, 4801, 4603, 4409, 4219, 4033, 3851, 3673, 3499, 3329, 3163, 3001, 2843, 2689, 2539, 2393, 2251, 2113, 1979, 1849, 1723, 1601, 1483, 1369, 1259, 1153, 1051, 953, 859, 769, 683, 601, 523, 449, 379, 313, 251, 193, 139, 89, 43, 1, -37, -71, -101 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

A "prime-generating" polynomial: This polynomial generates 92 primes (57 being distinct) for n from 0 to 99 (in fact the next seven terms are still primes but we keep the range 0-99, customary for comparisons), just three primes fewer than the record held by Euler's polynomial for n = m-35, which is m^2 - 69*m + 1231 (see the link below).

The nonprime terms in the first 100 are 1, 1369 = 37^2, 1849 = 43^2, 4033 = 37*109 (all taken twice).

Setting n = 2*m+54 we obtain the polynomial 8*m^2 + 8*m - 197, which generates 31 primes in a row starting from m = 0 (the polynomial 8*m^2 - 488*m + 7243 generates the same 31 primes, but in reverse order).

From Charles Kusniec, Nov 11 2016: The substitution n = m+53 converts this polynomial to the simpler form 2*m^2-199.

REFERENCES

Joe L. Mott and Kermite Rose, Prime-Producing Cubic Polynomials in Lecture Notes in Pure and Applied Mathematics (Vol. 220), Marcel Dekker Inc., 2001, pages 281-317.

LINKS

Bruno Berselli, Table of n, a(n) for n = 0..1000

Joe L. Mott and Kermite Rose, Prime-Producing Cubic Polynomials

E. W. Weisstein, MathWorld: Prime-Generating Polynomial

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

FORMULA

G.f.: (5419-11048*x+5633*x^2)/(1-x)^3. - Bruno Berselli, May 18 2012

MAPLE

A211775:=n->2*n^2 - 212*n + 5419: seq(A211775(n), n=0..100); # Wesley Ivan Hurt, Jan 20 2017

MATHEMATICA

Table[2*n^2 - 212*n + 5419, {n, 0, 80}] (* Wesley Ivan Hurt, Aug 06 2017 *)

PROG

(MAGMA) [2*n^2-212*n+5419: n in [0..49]]; // Bruno Berselli, May 18 2012

(PARI) Vec((5419-11048*x+5633*x^2)/(1-x)^3+O(x^99)) \\ Charles R Greathouse IV, Oct 01 2012

(PARI) a(n) = 2*n^2 - 212*n + 5419 \\ Charles R Greathouse IV, Dec 19 2016

CROSSREFS

Sequence in context: A203711 A105654 A124410 * A116894 A124629 A222696

Adjacent sequences:  A211772 A211773 A211774 * A211776 A211777 A211778

KEYWORD

sign,easy

AUTHOR

Marius Coman, May 18 2012

EXTENSIONS

Edited by N. J. A. Sloane, Nov 12 2016

STATUS

approved

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Last modified January 19 18:20 EST 2019. Contains 319309 sequences. (Running on oeis4.)