cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A002309 Sum of fourth powers of first n odd numbers.

Original entry on oeis.org

1, 82, 707, 3108, 9669, 24310, 52871, 103496, 187017, 317338, 511819, 791660, 1182285, 1713726, 2421007, 3344528, 4530449, 6031074, 7905235, 10218676, 13044437, 16463238, 20563863, 25443544, 31208345, 37973546, 45864027, 55014652, 65570653, 77688014
Offset: 1

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Examples

			a(1) = 1^4 = 1.
a(2) = 1^4 + 3^4 = 82.
a(3) = 1^4 + 3^4 + 5^4 = 707.
		

References

  • F. E. Croxton and D. J. Cowden, Applied General Statistics. 2nd ed., Prentice-Hall, Englewood Cliffs, NJ, 1955, p. 742.
  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Programs

  • Maple
    A002309:=(1+76*z+230*z**2+76*z**3+z**4)/(z-1)**6; # conjectured by Simon Plouffe in his 1992 dissertation
  • Mathematica
    Table[(48*n^5 - 40*n^3 + 7*n)/15, {n, 0, 40}] (* Stefan Steinerberger, Apr 10 2006 *)
    s = 0; lst = {s}; Do[s += n^4; AppendTo[lst, s], {n, 1, 60, 2}]; lst (* Zerinvary Lajos, Jul 12 2009 *)
    Accumulate[Range[1,63,2]^4] (* Harvey P. Dale, Oct 24 2011 *)
    LinearRecurrence[{6,-15,20,-15,6,-1},{1,82,707,3108,9669,24310},20] (* Harvey P. Dale, Sep 29 2015 *)
  • PARI
    a(n)=(48*n^5-40*n^3+7*n)/15 \\ Charles R Greathouse IV, Apr 07 2016
    
  • Python
    def A002309(n): return n*(n**2*(6*n**2-5<<3)+7)//15 # Chai Wah Wu, Oct 02 2024

Formula

a(n) = (48*n^5 - 40*n^3 + 7*n)/15. - Ralf Stephan, Jan 29 2003
a(1)=1, a(2)=82, a(3)=707, a(4)=3108, a(5)=9669, a(6)=24310, a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6). - Harvey P. Dale, Oct 24 2011
a(n) = v(n,n-2) - v(n,n-1)*V(n,n-1), where v(n,k) and V(n,k) are the central factorial numbers of the first kind and the second kind, respectively, with odd indices. - Mircea Merca, Jan 25 2014
From Wolfdieter Lang, Mar 11 2017: (Start)
G.f.: x*(1 + 76*x + 230*x^2 + 76*x^3 + 1*x^4)/(1-x)^6.
E.g.f. (with offset 0): exp(x)*(1 + 81*x + 544*x^2/2! + 1232*x^3/3! + 1152*x^4/4! + 384*x^5/5!). (End)

Extensions

Definition changed by David A. Corneth, Mar 11 2017
Name clarified by Mohammed Yaseen, Jul 24 2023