OFFSET
0,2
LINKS
FORMULA
a(n) = n*(n + 31)/2.
If we define f(n,i,r) = Sum_{k=0..n-i} binomial(n,k) * Stirling1(n-k,i) * Product_{j=0..k-1} (-r-j), then a(n) = -f(n,n-1,16) for n>=1. - Milan Janjic, Dec 20 2008
a(n) = n + a(n-1) + 15 for n>0, a(0)=0. - Vincenzo Librandi, Aug 03 2010
a(0)=0, a(1)=16, a(2)=33; for n>2, a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3). - Harvey P. Dale, Jun 21 2012
a(n) = 16*n - floor(n/2) + floor(n^2/2). - Wesley Ivan Hurt, Jun 15 2013
From Amiram Eldar, Jan 11 2021: (Start)
Sum_{n>=1} (-1)^(n+1)/a(n) = 4*log(2)/31 - 7313175618421/159875362132200. (End)
From Elmo R. Oliveira, Nov 29 2024: (Start)
G.f.: x*(15*x - 16)/(x-1)^3.
E.g.f.: exp(x)*x*(32 + x)/2.
a(n) = A132773(n)/2. (End)
MATHEMATICA
Table[(n(n+31))/2, {n, 0, 50}] (* or *) LinearRecurrence[{3, -3, 1}, {0, 16, 33}, 50] (* Harvey P. Dale, Jun 21 2012 *)
PROG
(PARI) a(n)=n*(n+31)/2 \\ Charles R Greathouse IV, Oct 07 2015
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Omar E. Pol, Aug 28 2007
STATUS
approved