OFFSET
0,1
LINKS
T. D. Noe, Table of n, a(n) for n = 0..1000
L. B. W. Jolley, Summation of Series, Dover, 1961
Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1).
FORMULA
a(n) = 6 * A015219(n).
Sum_{n>=0} 1/a(n) = log(2)/4 = 0.17328679513998... [Jolley eq. 253. Typo fixed by Jaume Oliver Lafont, Jan 09 2009]
G.f.: 6*(1+x)*(x^2+30*x+1) / (x-1)^4. - R. J. Mathar, Apr 02 2011
Sum_{n>=0} (-1)^n/a(n) = (sqrt(2)-1)*Pi/8. - Amiram Eldar, Sep 17 2022
MATHEMATICA
Table[(4n+1)(4n+2)(4n+3), {n, 0, 49}] (* Vladimir Joseph Stephan Orlovsky, Jan 22 2012 *)
PROG
(Magma) [(4*n+1)*(4*n+2)*(4*n+3): n in [0..100]]; // Vincenzo Librandi, Apr 04 2011
(PARI) a(n)=(4*n+1)*(4*n+2)*(4*n+3) \\ Charles R Greathouse IV, Jun 17 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved