A133203 a(n) = a(n-1) + 8*n + 4, n > 2.

0, 1, 3, 31, 67, 111, 163, 223, 291, 367, 451, 543, 643, 751, 867, 991, 1123, 1263, 1411, 1567, 1731, 1903, 2083, 2271, 2467, 2671, 2883, 3103, 3331, 3567, 3811, 4063, 4323, 4591, 4867, 5151, 5443, 5743, 6051, 6367

Offset

0,3

Comments

Apart from {0,1} at the start, 15 of the first 30 are primes.

Links

Table of n, a(n) for n=0..39.

Formula

From R. J. Mathar, Sep 01 2008: (Start)

G.f.: x(1+25x^2-18x^3)/(1-x)^3.

a(n) = 4n^2+8n-29, n > 1. (End)

Example

fz(1)=0; fz(2)=1; fz(3)=3;
for k=4:n
fz(k)=fz(k-1)+8*k+4;
end
y=fz(n);

Mathematica

Join[{0, 1}, RecurrenceTable[{a[2]==3, a[n]==a[n-1]+8n+4}, a, {n, 40}]] (* Harvey P. Dale, Mar 16 2013 *)

Prog

(MATLAB) function y=fib(n)

Crossrefs

Sequence in context: A141966 A050833 A041207 * A062616 A289733 A244916

Adjacent sequences: A133200 A133201 A133202 * A133204 A133205 A133206

Keyword

nonn

Author

Matt Wynne (mattwyn(AT)verizon.net), Aug 27 2008

Extensions

More terms from R. J. Mathar, Sep 01 2008

Constraint on n added to the definition by R. J. Mathar, Jul 23 2009

Status

approved