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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A151556 Values of (n^5+47*n)/48 as n ranges over the numbers that are == +-1 mod 6. 0
1, 70, 357, 3366, 7748, 29597, 51604, 134113, 203475, 427344, 596471, 1094240, 1444702, 2413711, 3062718, 4778067, 5884949, 8712458, 10485145, 14894314, 17595816, 24172785, 28127672, 37588181, 43189063, 56391412, 64105419, 82063428, 92438690, 116334659 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

((n^5+47n)/48)^2 is the sum of the squares of the n^2 integers from (n^4-24n^2-25)/48 to (n^4+24n^2-73)/48. For example, when n=5, 70^2 is the sum of the 25 squares of the integers from 0 to 24.

LINKS

Table of n, a(n) for n=1..30.

Index entries for sequences related to sums of squares

FORMULA

a(n) = a(n-1)+5*a(n-2)-5*a(n-3)-10*a(n-4)+10*a(n-5)+10*a(n-6)-10*a(n-7)-5*a(n-8)+5*a(n-9)+a(n-10)-a(n-11). [R. J. Mathar, May 21 2009]

G.f.: x*(1 +69*x +282*x^2 +2664*x^3 +2957*x^4 +7494*x^5 +2957*x^6 +2664*x^7 +282*x^8 +69*x^9 +x^10)/((1+x)^5*(x-1)^6). [R. J. Mathar, May 21 2009]

a(n) = ((2*n-1)*(81*n^4-162*n^3+144*n^2-63*n+58)+(135*n^4-270*n^3+210*n^2-75*n+26)*(-1)^n)/32. - Tani Akinari, Oct 25 2014

MATHEMATICA

With[{nn=20}, (#^5+47#)/48&/@Sort[Join[6Range[0, nn]+1, 6Range[nn]-1]]] (* Harvey P. Dale, Nov 15 2011 *)

PROG

(MAGMA) [((2*n-1)*(81*n^4-162*n^3+144*n^2-63*n+58)+(135*n^4-270*n^3+210*n^2-75*n+26)*(-1)^n)/32: n in [1..30]]; // Vincenzo Librandi, Oct 25 2014

CROSSREFS

Cf. A007310, A097812, A001032.

Sequence in context: A174533 A174534 A295770 * A172222 A157369 A163434

Adjacent sequences:  A151553 A151554 A151555 * A151557 A151558 A151559

KEYWORD

nonn,easy

AUTHOR

Michael David Hirschhorn, May 21 2009

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 14 06:14 EST 2018. Contains 317162 sequences. (Running on oeis4.)