This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A152204 Triangle read by rows: T(n,k) = 2*n-4*k+5 (n >= 0, 1 <= k <= 1+floor(n/2)). 6
 1, 3, 5, 1, 7, 3, 9, 5, 1, 11, 7, 3, 13, 9, 5, 1, 15, 11, 7, 3, 17, 13, 9, 5, 1, 19, 15, 11, 7, 3, 21, 17, 13, 9, 5, 1, 23, 19, 15, 11, 7, 3, 25, 21, 17, 13, 9, 5, 1, 27, 23, 19, 15, 11, 7, 3, 29, 25, 21, 17, 13, 9, 5, 1, 31, 27, 23, 19, 15, 11, 7, 3, 33 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS All terms are odd, decreasing across rows. Row sums = A000217, the triangular numbers. From Johannes W. Meijer, Sep 08 2013: (Start) Triangle read by rows formed from the antidiagonals of triangle A099375. The alternating row sums equal A098181(n). (End) LINKS Nathaniel Johnston, Rows n = 0..200 of irregular triangle, flattened FORMULA By columns, odd terms in every column, n-th column starts at row (2*n). From Johannes W. Meijer, Sep 08 2013: (Start) T(n, k) = A099375(n-k+1, k-1), n >= 0 and 1 <= k <= 1+floor(n/2)). T(n, k) = A158405(n+1, n-2*k+2). (End) EXAMPLE First few rows of the triangle = 1 3 5  1 7  3 9  5  1 11 7  3 13 9  5  1 15 11 7  3 17 13 9  5 1 19 15 11 7 3 21 17 13 9 5 1 ... MAPLE T := proc(n, k) return 2*n-4*k+5: end: seq(seq(T(n, k), k=1..1+floor(n/2)), n=0..20); # Nathaniel Johnston, May 01 2011 CROSSREFS Cf. A000217. Sequence in context: A320051 A158858 A202356 * A114216 A208509 A086233 Adjacent sequences:  A152201 A152202 A152203 * A152205 A152206 A152207 KEYWORD nonn,tabf,easy AUTHOR Gary W. Adamson, Nov 29 2008 EXTENSIONS Edited by N. J. A. Sloane, Sep 25 2010, following a suggestion from Emeric Deutsch Offset corrected by Johannes W. Meijer, Sep 07 2013 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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified October 18 07:58 EDT 2018. Contains 316307 sequences. (Running on oeis4.)