login
This site is supported by donations to The OEIS Foundation.

 

Logo

Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing.
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A196513 a(n) = 1*4*7 + 4*7*10 + 7*10*13 + ... (n terms). 1
0, 28, 308, 1218, 3298, 7250, 13938, 24388, 39788, 61488, 91000, 129998, 180318, 243958, 323078, 420000, 537208, 677348, 843228, 1037818, 1264250, 1525818, 1825978, 2168348, 2556708, 2995000, 3487328, 4037958, 4651318, 5331998, 6084750 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

REFERENCES

Jolley, Summation of Series, Dover (1961), eq (49) page 10.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..10000

Index entries for linear recurrences with constant coefficients, signature (5,-10,10,-5,1)

FORMULA

a(n) = ((3*n-2)*(3*n+1)*(3*n+4)*(3*n+7) + 56)/12 = n*(3*n+5)*(9*n^2 + 15*n - 10)/4 = Sum_{i=1..n} (3*i-2)*(3*i+1)*(3*i+4).

G.f.: -2*x*(14 + 84*x - 21*x^2 + 4*x^3) / (x-1)^5.

PROG

(MAGMA) [n*(3*n+5)*(9*n^2+15*n-10)/4 : n in [0..30]]; // Vincenzo Librandi, Oct 05 2011

CROSSREFS

Sequence in context: A156711 A107942 A219172 * A042520 A022688 A125416

Adjacent sequences:  A196510 A196511 A196512 * A196514 A196515 A196516

KEYWORD

nonn,easy

AUTHOR

R. J. Mathar, Oct 03 2011

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 14 01:41 EST 2019. Contains 329978 sequences. (Running on oeis4.)