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A172047
n*(n+1)*(15*n^2-n-8)/12.
1
0, 1, 25, 124, 380, 905, 1841, 3360, 5664, 8985, 13585, 19756, 27820, 38129, 51065, 67040, 86496, 109905, 137769, 170620, 209020, 253561, 304865, 363584, 430400, 506025, 591201, 686700, 793324, 911905, 1043305, 1188416, 1348160, 1523489
OFFSET
0,3
COMMENTS
This sequence is related to A007587 by a(n) = n*A007587(n)-sum(i=0..n-1, A007587(i)).
This is the case d=5 in the general formula n*(n*(n+1)*(2*d*n-2*d+3)/6)-sum(i=0..n-1, i*(i+1)*(2*d*i-2*d+3)/6) = n*(n+1)*(3*d*n^2-d*n+4*n-2*d+2)/12. - Bruno Berselli, Dec 07 2010
The inverse binomial transform yields 0, 1, 23, 52, 30, 0, 0 (0 continued). - R. J. Mathar, Dec 09 2010
LINKS
B. Berselli, A description of the recursive method in Comments lines: website Matem@ticamente (in Italian).
FORMULA
G.f.: -x*(1+20*x+9*x^2)/(x-1)^5. - R. J. Mathar, Dec 09 2010
a(n)-a(-n) = A063521(n). - Bruno Berselli, Aug 26 2011
MATHEMATICA
CoefficientList[Series[x (1 + 20 x + 9 x^2)/(1 - x)^5, {x, 0, 40}], x] (* Vincenzo Librandi, Jan 01 2014 *)
PROG
(Magma) [n*(n+1)*(15*n^2-n-8)/12: n in [0..50]]; // Vincenzo Librandi, Jan 01 2014
CROSSREFS
Cf. A007587.
Sequence in context: A030081 A075047 A360640 * A304422 A280390 A225388
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Jan 24 2010
STATUS
approved