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!)
 A140168 Triangle read by rows, iterates of X * [1,0,0,0,...]; where X = an infinite bidiagonal matrix with [2, -1, 2, -1, 2,...] in the main diagonal, [1, 1, 1,...] in the subdiagonal and rest zeros. 1
 1, 2, 1, 4, 1, 1, 8, 3, 3, 1, 16, 5, 9, 2, 1, 32, 11, 23, 7, 4, 1, 64, 21, 57, 16, 15, 3, 1, 128, 43, 135, 41, 46, 12, 5, 1, 256, 85, 313, 94, 133, 34, 22, 4, 1, 512, 171, 711, 219, 360, 99, 78, 18, 6, 1, 1024, 341, 1593, 492, 939, 261, 255, 60, 30, 5, 1, 2048, 683, 3527, 1101 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Row sums = A105476 starting (1, 3, 6, 15, 33, 78, 177,...). LINKS FORMULA Triangle read by rows, iterates of X * [1,0,0,0,...]; where X = an infinite bidiagonal matrix with [2, -1, 2, -1, 2,...] in the main diagonal, [1, 1, 1,...] in the subdiagonal and rest zeros. EXAMPLE First few rows of the triangle are: 1; 2, 1; 4, 1, 1; 8, 3, 3, 1; 16, 5, 9, 2, 1; 32, 11, 23, 7, 4, 1; 64, 21, 57, 16, 15, 3, 1; 128, 43, 135, 41, 46, 12, 5, 1; 256, 85, 313, 94, 133, 34, 22, 4, 1; 512, 171, 711, 219, 360, 99, 78, 18, 6, 1; ... CROSSREFS Cf. A105476. Sequence in context: A117352 A137710 A068009 * A059119 A305333 A127772 Adjacent sequences:  A140165 A140166 A140167 * A140169 A140170 A140171 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, May 10 2008 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 12 20:12 EST 2019. Contains 329961 sequences. (Running on oeis4.)