|
| |
| |
|
|
|
0, 15, 60, 135, 240, 375, 540, 735, 960, 1215, 1500, 1815, 2160, 2535, 2940, 3375, 3840, 4335, 4860, 5415, 6000, 6615, 7260, 7935, 8640, 9375, 10140, 10935, 11760, 12615, 13500, 14415, 15360, 16335, 17340, 18375, 19440, 20535, 21660, 22815
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
0,2
|
|
|
COMMENTS
|
Number of edges in a complete 6-partite graph of order 6n, K_n,n,n,n,n,n.
|
|
|
LINKS
|
Table of n, a(n) for n=0..39.
Index entries for linear recurrences with constant coefficients, signature (3,-3,1).
|
|
|
FORMULA
|
a(n) = A000290(n)*15 = A033428(n)*5 = A033429(n)*3. - Omar E. Pol, Dec 13 2008
a(n) = A008587(n)*A008585(n). - Reinhard Zumkeller, Apr 12 2010
a(n) = a(n-1) + 30*n - 15 for n>0, a(0)=0. - Vincenzo Librandi, Dec 15 2010
a(n) = A022272(n) + A022272(-n). - Bruno Berselli, Mar 31 2015
a(n) = t(6*n) - 6*t(n), where t(i) = i*(i+k)/2 for any k. Special case (k=1): a(n) = A000217(6*n) - 6*A000217(n). - Bruno Berselli, Aug 31 2017
|
|
|
MAPLE
|
seq(bell(4, j)*(j-2)^2, j = 2 .. 41) ; # Zerinvary Lajos, Nov 29 2007
|
|
|
PROG
|
(PARI) a(n)=15*n^2 \\ Charles R Greathouse IV, Jun 17 2017
|
|
|
CROSSREFS
|
Cf. A000217, A000290, A022272, A033428, A033581, A033583, A033429.
Sequence in context: A288747 A223344 A206238 * A005945 A223337 A110755
Adjacent sequences: A064758 A064759 A064760 * A064762 A064763 A064764
|
|
|
KEYWORD
|
nonn,easy
|
|
|
AUTHOR
|
Roberto E. Martinez II, Oct 18 2001
|
|
|
STATUS
|
approved
|
| |
|
|
