The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A261995 The first of four consecutive positive integers the sum of the squares of which is equal to the sum of the squares of twenty-one consecutive positive integers. 2
 42, 123, 315, 1827, 4659, 13650, 34794, 201114, 512610, 1501539, 3827187, 22120875, 56382603, 165155802, 420955938, 2433095298, 6201573882, 18165636843, 46301326155, 267618362067, 682116744579, 1998054897090, 5092724921274, 29435586732234, 75026640329970 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS For the first of the corresponding twenty-one consecutive positive integers, see A261996. LINKS Colin Barker, Table of n, a(n) for n = 1..1000 Index entries for linear recurrences with constant coefficients, signature (1,0,0,110,-110,0,0,-1,1). FORMULA G.f.: -3*x*(6*x^8+8*x^6+27*x^5-596*x^4+504*x^3+64*x^2+27*x+14) / ((x-1)*(x^8-110*x^4+1)). EXAMPLE 42 is in the sequence because 42^2 + ... + 45^2 = 7574 = 8^2 + ... + 28^2. PROG (PARI) Vec(-3*x*(6*x^8+8*x^6+27*x^5-596*x^4+504*x^3+64*x^2+27*x+14)/((x-1)*(x^8-110*x^4+1)) + O(x^40)) CROSSREFS Cf. A157092, A246642, A261996. Sequence in context: A113518 A044293 A044674 * A298236 A299362 A304613 Adjacent sequences: A261992 A261993 A261994 * A261996 A261997 A261998 KEYWORD nonn,easy AUTHOR Colin Barker, Sep 08 2015 STATUS approved

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

Last modified May 21 04:01 EDT 2024. Contains 372720 sequences. (Running on oeis4.)