This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A062684 Number of addition triangles with apex n (version 1). 2
 1, 2, 3, 5, 7, 10, 13, 18, 23, 29, 37, 46, 55, 68, 81, 96, 115, 135, 155, 183, 211, 241, 277, 317, 357, 407, 457, 513, 577, 645, 713, 799, 885, 977, 1079, 1191, 1305, 1438, 1571, 1717, 1875, 2048, 2221, 2423, 2625, 2840, 3077, 3333, 3589, 3876, 4163 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS An addition triangle has any set of positive numbers as base; other rows are formed by adding pairs of adjacent numbers. Reversing the base counts as a different triangle. LINKS EXAMPLE For n = 5: ..5.......5................................. .2,3.....3,2.....5.....5.....5.....5........ 1,1,2...2,1,1...4,1...1,4...2,3...3,2...5... with seven different bases, so a(5) = 7. CROSSREFS Cf. A028307, A066411, see A062896 for version 2. Sequence in context: A115001 A008766 A103232 * A033485 A026811 A001401 Adjacent sequences:  A062681 A062682 A062683 * A062685 A062686 A062687 KEYWORD easy,nonn AUTHOR Naohiro Nomoto, Feb 11 2002 EXTENSIONS Extended and edited by John W. Layman, Feb 14 2002 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 February 17 10:59 EST 2019. Contains 320219 sequences. (Running on oeis4.)