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!)
 A220522 Number of toothpicks and D-toothpicks after n-th stage in the D-toothpick "narrow" triangle of the third kind. 13
 0, 1, 3, 7, 11, 15, 19, 26, 34, 38, 42, 50, 62, 70, 78, 91, 107, 111, 115, 123, 135, 151, 167, 187, 211, 223, 231, 247, 275, 291, 307, 332, 364, 368, 372, 380, 392, 408, 424, 446, 478, 504, 524, 548, 588, 620, 660, 701, 749, 769, 777 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS The structure is essentially one of the oblique wedges of several D-toothpick structures. For more information see A220500. First differs from A194442 at a(47). The first differences (A220523) give the number of toothpicks or D-toothpicks added at n-th stage. LINKS Omar E. Pol, Illustration of the structure after 32 stages Omar E. Pol, Illustration of the structure after 64 stages N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS CROSSREFS Cf. A047999, A139250, A194270, A194700, A194440, A194442, A194444, A220496, A220500, A220523. Sequence in context: A277675 A220496 A194442 * A220526 A034934 A191151 Adjacent sequences:  A220519 A220520 A220521 * A220523 A220524 A220525 KEYWORD nonn AUTHOR Omar E. Pol, Dec 15 2012 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 8 02:08 EST 2019. Contains 329850 sequences. (Running on oeis4.)