|
Search: id:A152743
|
|
|
| A152743 |
|
6 times pentagonal numbers: 3n(3n-1). |
|
+0
3
|
|
| 0, 6, 30, 72, 132, 210, 306, 420, 552, 702, 870, 1056, 1260, 1482, 1722, 1980, 2256, 2550, 2862, 3192, 3540, 3906, 4290, 4692, 5112, 5550, 6006, 6480, 6972, 7482, 8010, 8556, 9120, 9702, 10302, 10920, 11556, 12210, 12882, 13572, 14280
(list; graph; listen)
|
|
|
OFFSET
|
0,2
|
|
|
FORMULA
|
a(n) = 9n^2 - 3n = A000326(n)*6.
a(n) = A049450(n)*3 = A062741(n)*2. [From Omar E. Pol (info(AT)polprimos.com), Dec 15 2008]
a(n)=18*n+a(n-1)-30 (with a(1)=0) [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Nov 13 2009]
|
|
EXAMPLE
|
For n=2, a(2)=18*2+0-30=6; n=3, a(3)=18*3+6-30=30; n=4, a(4)=18*4+30-30=72 [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Nov 13 2009]
|
|
MATHEMATICA
|
s=0; lst={s}; Do[s+=n; AppendTo[lst, s], {n, 6, 7!, 18}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Apr 03 2009]
|
|
CROSSREFS
|
Cf. A000326, A152734, A152744.
Cf. A049450, A062741. [From Omar E. Pol (info(AT)polprimos.com), Dec 15 2008]
Sequence in context: A056835 A056836 A163640 this_sequence A038039 A050972 A002444
Adjacent sequences: A152740 A152741 A152742 this_sequence A152744 A152745 A152746
|
|
KEYWORD
|
easy,nonn,new
|
|
AUTHOR
|
Omar E. Pol (info(AT)polprimos.com), Dec 12 2008
|
|
|
Search completed in 0.002 seconds
|
