This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A008528 Coordination sequence for 4-dimensional RR-centered di-isohexagonal orthogonal lattice. 3
 1, 18, 102, 318, 732, 1410, 2418, 3822, 5688, 8082, 11070, 14718, 19092, 24258, 30282, 37230, 45168, 54162, 64278, 75582, 88140, 102018, 117282, 133998, 152232, 172050, 193518, 216702, 241668 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 REFERENCES M. O'Keeffe, Coordination sequences for lattices, Zeit. f. Krist., 210 (1995), 905-908. LINKS Vincenzo Librandi, Table of n, a(n) for n = 0..1000 M. O'Keeffe, Coordination sequences for lattices, Zeit. f. Krist., 210 (1995), 905-908. [Annotated scanned copy] p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 13.0px 'Helvetica Neue Light'; color: #000000; -webkit-text-stroke: #000000} p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 13.0px 'Helvetica Neue Light'; color: #000000; -webkit-text-stroke: #000000; min-height: 16.0px} span.s1 {font-kerning: none} Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1). FORMULA a(n) = n*(11*n^2+7) with n>0, a(0)=1 (see MAPLE line). G.f. 1 + 6*x*(3 + 5*x + 3*x^2) / (1-x)^4. - R. J. Mathar, Sep 04 2011 MAPLE [ seq( 11*k^3+7*k, k=1..40 ) ]; # apart from the first term MATHEMATICA CoefficientList[Series[1+6*x*(3+5*x+3*x^2)/(1-x)^4, {x, 0, 30}], x] (* Vincenzo Librandi, Jun 19 2012 *) LinearRecurrence[{4, -6, 4, -1}, {1, 18, 102, 318, 732}, 30] (* Harvey P. Dale, Apr 27 2017 *) PROG (MAGMA) I:=[1, 18, 102, 318, 732]; [n le 5 select I[n] else 4*Self(n-1)-6*Self(n-2)+4*Self(n-3)-Self(n-4): n in [1..30]]; // Vincenzo Librandi, Jun 19 2012 CROSSREFS Sequence in context: A140198 A107600 A229326 * A020881 A285043 A223241 Adjacent sequences:  A008525 A008526 A008527 * A008529 A008530 A008531 KEYWORD nonn,easy AUTHOR 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.

Last modified March 20 12:03 EDT 2018. Contains 300983 sequences. (Running on oeis4.)