login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A159797 Triangle read by rows in which row n lists n+1 terms, starting with n, such that the difference between successive terms is equal to n-1. 33
0, 1, 1, 2, 3, 4, 3, 5, 7, 9, 4, 7, 10, 13, 16, 5, 9, 13, 17, 21, 25, 6, 11, 16, 21, 26, 31, 36, 7, 13, 19, 25, 31, 37, 43, 49, 8, 15, 22, 29, 36, 43, 50, 57, 64, 9, 17, 25, 33, 41, 49, 57, 65, 73, 81, 10, 19, 28, 37, 46, 55, 64, 73, 82, 91, 100, 11, 21, 31, 41, 51, 61, 71, 81, 91, 101 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,4

COMMENTS

Note that the last term of the n-th row is the n-th square A000290(n).

See also A162611, A162614 and A162622.

The triangle sums, see A180662 for their definitions, link the triangle A159797 with eleven sequences, see the crossrefs. [From Johannes W. Meijer, May 20 2011]

LINKS

David Applegate, Omar E. Pol and N. J. A. Sloane, The Toothpick Sequence and Other Sequences from Cellular Automata

N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS

FORMULA

Given m = floor( (sqrt(8*n+1)-1)/2 ), then a(n) = m + (n - m*(m+1)/2)*(m-1) [From Carl R. White (oeisfan(AT)phodd.net), Jul 24 2010]

EXAMPLE

Triangle begins:

0;

1, 1;

2, 3, 4;

3, 5, 7, 9;

4, 7,10,13,16;

5, 9,13,17,21,25;

6,11,16,21,26,31,36;

MAPLE

A159797:=proc(n) local m: m := floor( (sqrt(8*n+1)-1)/2 ): A159797(n):= m + (n - m*(m+1)/2)*(m-1) end: seq(A159797(n), n=0..75); [From Johannes W. Meijer, May 20 2011]

PROG

(Other) /*GNU bc*/ scale=0; for(n=0; n<76; n++){m=(sqrt(8*n+1)-1)/2; print m+(n-m*(m+1)/2)*(m-1), ", "}; print"\n" [From Carl R. White (oeisfan(AT)phodd.net), Jul 24 2010]

CROSSREFS

Cf. A000290, A001477, A081493, A159798, A162609, A162610, A162611, A162614, A162622.

Cf.: A006002 (row sums). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jul 17 2009]

Cf. A163282, A163283, A163284, A163285. [From Omar E. Pol (info(AT)polprimos.com), Nov 18 2009]

From Johannes W. Meijer, May 20 2011: (Start)

Triangle sums (see the comments): A006002 (Row1), A050187 (Row2), A058187 (Related to Kn11, Kn12, Kn13, Fi1 and Ze1), A006918 (Related to Kn21, Kn22, Kn23, Fi2 and Ze2), A000330 (Kn3), A016061 (Kn4), A190717 (Related to Ca1 and Ze3), A144677 (Related to Ca2 and Ze4), A000292 (Related to Ca3, Ca4, Gi3 and Gi4) A190718 (Related to Gi1) and A144678 (Related to Gi2). (End)

Sequence in context: A141128 A160180 A078908 * A152920 A080383 A086369

Adjacent sequences:  A159794 A159795 A159796 * A159798 A159799 A159800

KEYWORD

easy,nonn,tabl

AUTHOR

Omar E. Pol (info(AT)polprimos.com), Jul 09 2009

EXTENSIONS

Edited by Omar E. Pol (info(AT)polprimos.com), Jul 18 2009

More terms from Omar E. Pol (info(AT)polprimos.com), Nov 18 2009

More terms from Carl R. White (oeisfan(AT)phodd.net), Jul 24 2010

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 13 12:58 EST 2012. Contains 205482 sequences.