|
|
A185019
|
|
a(n) = n*(14*n-3).
|
|
19
|
|
|
0, 11, 50, 117, 212, 335, 486, 665, 872, 1107, 1370, 1661, 1980, 2327, 2702, 3105, 3536, 3995, 4482, 4997, 5540, 6111, 6710, 7337, 7992, 8675, 9386, 10125, 10892, 11687, 12510, 13361, 14240, 15147, 16082, 17045, 18036, 19055, 20102, 21177, 22280, 23411, 24570
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,2
|
|
LINKS
|
|
|
FORMULA
|
G.f.: x*(11+17*x)/(1-x)^3.
|
|
MATHEMATICA
|
CoefficientList[Series[x (11 + 17 x)/(1 - x)^3, {x, 0, 45}], x] (*Vincenzo Librandi_, Aug 18 2013 *)
|
|
PROG
|
(PARI) for(n=0, 42, print1(n*(14*n-3)", "));
(Magma) [n*(14*n-3): n in [0..42]];
(Magma) I:=[0, 11, 50]; [n le 3 select I[n] else 3*Self(n-1)-3*Self(n-2)+Self(n-3): n in [1..50]]; // Vincenzo Librandi, Aug 18 2013
|
|
CROSSREFS
|
Cf. A195020 (vertices of the numerical spiral in link).
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|