This site is supported by donations to The OEIS Foundation.

 Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing. Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A124847 Triangle read by rows: T(n,k) = k(k+1)*binomial(n-1, k-1)/2 (1 <= k <= n). 0
 1, 1, 3, 1, 6, 6, 1, 9, 18, 10, 1, 12, 36, 40, 15, 1, 15, 60, 100, 75, 21, 1, 18, 90, 200, 225, 126, 28, 1, 21, 126, 350, 525, 441, 196, 36, 1, 24, 168, 560, 1050, 1176, 784, 288, 45, 1, 27, 216, 840, 1890, 2646, 2352, 1296, 405, 55, 1, 30, 270, 1200, 3150, 5292, 5880 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Sum of row n gives A049611(n). Triangle is P*A, where P is the Pascal triangle written as a lower triangular matrix and C is the diagonal matrix of the triangular numbers 1, 3, 6, 10, .... LINKS EXAMPLE First few rows of the triangle:   1;   1,   3;   1,   6,   6;   1,   9,  18,  10;   1,  12,  36,  40,  15;   1,  15,  60, 100,  75,  21;   ... Sum of row 3 = 38 = (1 + 9 + 18 + 10) = A049611(3). MAPLE T:=(n, k)->k*(k+1)*binomial(n-1, k-1)/2: for n from 1 to 12 do seq(T(n, k), k=1..n) od; # yields sequence in triangular form CROSSREFS Cf. A049611. Sequence in context: A210593 A179069 A235706 * A249251 A127893 A127895 Adjacent sequences:  A124844 A124845 A124846 * A124848 A124849 A124850 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, Nov 10 2006 EXTENSIONS Edited by N. J. A. Sloane, Nov 24 2006 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 December 15 22:02 EST 2019. Contains 330012 sequences. (Running on oeis4.)