OFFSET
0,2
LINKS
Bruno Berselli, Table of n, a(n) for n = 0..300
FORMULA
a(n) = ((n^2-2)*n^(n+1)+1)/(n-1)^2 for n > 1; a(0)=1, a(1)=3.
EXAMPLE
a(4) = 1593 because 1593 = 1+2*4+3*4^2+4*4^3+5*4^4.
MATHEMATICA
Join[{1, 3}, Table[(((n^2 - 2) n^(n + 1) + 1) / (n - 1)^2), {n, 2, 20}]] (* Vincenzo Librandi, Aug 19 2013 *)
PROG
(Magma) [&+[(k+1)*n^k: k in [0..n]]: n in [0..17]];
CROSSREFS
KEYWORD
nonn
AUTHOR
Bruno Berselli, Apr 15 2011
STATUS
approved