OFFSET
0,2
COMMENTS
Sum of n-th row of triangle of even numbers: (2, 4), (6, 8, 10, 12), (14, 16, 18, 20, 22, 24), (26, 28, 30, 32, 34, 36, 38, 40), ..., where n-th row contains 2n terms.
Also, integer values of n^3/2 + n. - Arkadiusz Wesolowski, Jul 20 2012
LINKS
Harry J. Smith, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1).
FORMULA
a(n) = 6*A005900(n).
G.f.: 6*x*(1 + x)^2/(1 - x)^4. - Colin Barker, Apr 20 2012
EXAMPLE
a(3) = 114 = 14 + 16 + 18 + 20 + 22 + 24.
MAPLE
MATHEMATICA
Table[2*n*(2*n^2 + 1), {n, 0, 5!}] (* Vladimir Joseph Stephan Orlovsky, Dec 04 2010 *)
LinearRecurrence[{4, -6, 4, -1}, {0, 6, 36, 114}, 40] (* Harvey P. Dale, Feb 04 2023 *)
PROG
(PARI) { for (n=0, 1000, write("b061804.txt", n, " ", 2*n*(2*n^2 + 1)) ) } \\ Harry J. Smith, Jul 28 2009
(Python)
def A061804(n): return n*((n**2<<2) + 2) # Chai Wah Wu, Aug 29 2022
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Amarnath Murthy, May 28 2001
EXTENSIONS
More terms from Larry Reeves (larryr(AT)acm.org) and Alford Arnold, May 29 2001
Better description from Dean Hickerson, Jun 05 2001
STATUS
approved