This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A072474 Sum of next n squares. 11
 1, 13, 77, 294, 855, 2071, 4403, 8492, 15189, 25585, 41041, 63218, 94107, 136059, 191815, 264536, 357833, 475797, 623029, 804670, 1026431, 1294623, 1616187, 1998724, 2450525, 2980601, 3598713, 4315402, 5142019, 6090755, 7174671 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS FORMULA a(n) = k(k+1)(2k+1)/6 - r(r+1)(2r+1)/6, where k = n(n+1)/2 and r = n(n-1)/2. a(n) = (n/12) *(3n^2+1)*(n^2+2). - Benoit Cloitre, Jun 26 2002 G.f.: x*(1+3*x+x^2)*(1+4*x+x^2)/(1-x)^6. - Colin Barker, Mar 23 2012 EXAMPLE 1^2 = 1; 2^2 + 3^2 = 13; 4^2 + 5^2 + 6^2 = 77; ... MATHEMATICA Table[Sum[ i^2, {i, n(n - 1)/2 + 1, n(n + 1)/2}], {n, 1, 35}] PROG (PARI) for(n=1, 50, print1(n*(3*n^2+1)*(n^2+2)/12, ", ")) CROSSREFS Cf. A072475, A050410. Sequence in context: A044200 A044581 A126423 * A186103 A194713 A047638 Adjacent sequences:  A072471 A072472 A072473 * A072475 A072476 A072477 KEYWORD nonn,easy AUTHOR Amarnath Murthy, Jun 20 2002 EXTENSIONS Edited by Robert G. Wilson v, Jun 21 2002 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.

Last modified October 13 20:38 EDT 2019. Contains 327981 sequences. (Running on oeis4.)