|
|
A178190
|
|
Sum 7^((k^2+3k)/2) from k=1 to n.
|
|
1
|
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
Series of the kind m^((k^2+3k)/2) from k=1 to n was studied by Bernoulli and Euler.
|
|
LINKS
|
|
|
MAPLE
|
|
|
MATHEMATICA
|
aa = {}; m = 7; sum = 0; Do[sum = sum + m^((n + 3) n/2); AppendTo[aa, sum], {n, 1, 20}]; aa (* Artur Jasinski *)
Table[Sum[7^((k^2 + 3 k)/2), {k, n}], {n, 10}] (* Wesley Ivan Hurt, Apr 01 2014 *)
|
|
PROG
|
(PARI) a(n) = sum(k=1, n, 7^((k^2+3*k)/2)); \\ Michel Marcus, Sep 09 2013
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|