A161176 a(n) = 4n^2 - 10n + 107.

107, 101, 103, 113, 131, 157, 191, 233, 283, 341, 407, 481, 563, 653, 751, 857, 971, 1093, 1223, 1361, 1507, 1661, 1823, 1993, 2171, 2357, 2551, 2753, 2963, 3181, 3407, 3641, 3883, 4133, 4391, 4657, 4931, 5213, 5503, 5801, 6107

Offset

0,1

Comments

Northwest corner values of Ulam spiral with 101 at center.

Links

Table of n, a(n) for n=0..40.

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

Formula

a(n) = 3*a(n-1)-3*a(n-2)+a(n-3). G.f.: -(107-220*x+121*x^2)/(x-1)^3. - R. J. Mathar, Jul 24 2009

Mathematica

LinearRecurrence[{3, -3, 1}, {107, 101, 103}, 50] (* Harvey P. Dale, Jun 05 2012 *)

Prog

(PARI) a(n)=4*n^2-10*n+107 \\ Charles R Greathouse IV, Jun 17 2017

Crossrefs

Sequence in context: A160487 A178546 A096712 * A161372 A099652 A344803

Adjacent sequences: A161173 A161174 A161175 * A161177 A161178 A161179

Keyword

nonn,easy

Author

Milton L. Brown (miltbrown(AT)earthlink.net), Jun 05 2009, Jul 21 2009

Status

approved