This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A128077 A128064 * A002260. 3
 1, 1, 4, 1, 2, 9, 1, 2, 3, 16, 1, 2, 3, 4, 25, 1, 2, 3, 4, 5, 36, 1, 2, 3, 4, 5, 6, 49, 1, 2, 3, 4, 5, 6, 7, 64 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Row sums = the pentagonal numbers, A000326: 1, 5, 12, 22, 35, 51,... LINKS FORMULA A128064 * A002260 as infinite lower triangular matrices. Triangle read by rows, a(1) = 1; n-th row = first (n-1) terms of (1, 2, 3...) followed by n^2. EXAMPLE First few rows of the triangle are: 1; 1, 4; 1, 2, 9; 1, 2, 3, 16; 1, 2, 3, 4, 25; ... CROSSREFS Cf. A128064, A002260, A000326, A128078. Sequence in context: A133883 A279816 A004160 * A128078 A264922 A233528 Adjacent sequences:  A128074 A128075 A128076 * A128078 A128079 A128080 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, Feb 14 2007 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 March 26 20:37 EDT 2019. Contains 321534 sequences. (Running on oeis4.)