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A162265
a(n) = (2*n^3 + 5*n^2 - 5*n)/2.
2
1, 13, 42, 94, 175, 291, 448, 652, 909, 1225, 1606, 2058, 2587, 3199, 3900, 4696, 5593, 6597, 7714, 8950, 10311, 11803, 13432, 15204, 17125, 19201, 21438, 23842, 26419, 29175, 32116, 35248, 38577, 42109, 45850, 49806, 53983, 58387, 63024, 67900
OFFSET
1,2
FORMULA
Row sums from A154684: a(n) = Sum_{m=1..n} 2*m*n+m+n-3.
G.f.: x*(1+9*x-4*x^2)/(1-x)^4. - Vincenzo Librandi, Mar 05 2012
a(n) = 4*a(n-1) -6*a(n-2) +4*a(n-3) -a(n-4). - Vincenzo Librandi, Mar 05 2012
MAPLE
A162265:=n->(2*n^3 + 5*n^2 - 5*n)/2: seq(A162265(n), n=1..60); # Wesley Ivan Hurt, Apr 11 2017
MATHEMATICA
LinearRecurrence[{4, -6, 4, -1}, {4, 19, 51, 106}, 50] (* or *) CoefficientList[Series[(1+9*x-4*x^2)/(1-x)^4, {x, 0, 40}], x] (* Vincenzo Librandi, Mar 05 2012 *)
Table[(2n^3+5n^2-5n)/2, {n, 40}] (* Harvey P. Dale, May 25 2023 *)
PROG
(PARI) 5*binomial(n, 2)+n^3 \\ Charles R Greathouse IV, Jan 11 2012
(Magma) [(2*n^3 + 5*n^2 - 5*n)/2 : n in [1..50]]; // Wesley Ivan Hurt, May 07 2021
CROSSREFS
Cf. A154684.
Sequence in context: A081301 A159527 A139277 * A233298 A243028 A242544
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Jun 29 2009
STATUS
approved