The OEIS is supported by the many generous donors to the OEIS Foundation.

 Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”). Other ways to Give
 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A100178 Structured hexagonal diamond numbers (vertex structure 5). 10
 1, 8, 29, 72, 145, 256, 413, 624, 897, 1240, 1661, 2168, 2769, 3472, 4285, 5216, 6273, 7464, 8797, 10280, 11921, 13728, 15709, 17872, 20225, 22776, 25533, 28504, 31697, 35120, 38781, 42688, 46849, 51272, 55965, 60936, 66193, 71744, 77597, 83760, 90241, 97048, 104189 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Row 1 of the convolution array A213838. [Clark Kimberling, Jul 05 2012] LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..10000 FORMULA a(n) = (1/6)*(8*n^3-6*n^2+4*n). G.f.: x*(1+4*x+3*x^2)/(1-4*x+6*x^2-4*x^3+x^4). - Colin Barker, Jan 04 2012 PROG (Magma) [(1/6)*(8*n^3-6*n^2+4*n): n in [1..40]]; // Vincenzo Librandi, Aug 03 2011 CROSSREFS Cf. A000578 = alternate vertex; A000447 = structured diamonds; A100145 for more on structured numbers. Sequence in context: A244244 A037157 A288115 * A106113 A299260 A290312 Adjacent sequences: A100175 A100176 A100177 * A100179 A100180 A100181 KEYWORD nonn,easy AUTHOR James A. Record (james.record(AT)gmail.com), Nov 07 2004 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 November 30 02:32 EST 2022. Contains 358431 sequences. (Running on oeis4.)