The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A298270 Triangular numbers that for some k are also the sum of the first k composites. 1
 0, 10, 78, 153, 946, 177310, 450775, 13595505, 150988753, 4478601403, 5409300078, 5589152128, 76060335351, 248156250265, 1793751529485, 176149383165876, 187718592284301, 233626949305596, 11362376565228270, 18886935830647605, 1943937379018997076 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Table of n, a(n) for n=1..21. EXAMPLE 10 is a term because 10 = 1 + 2 + 3 + 4 = 4 + 6. PROG (PARI) lista(nn) = {my(s=0); forcomposite(n=0, nn, if(ispolygonal(s, 3), print1(s, ", ")); s += n; ); } \\ after Michel Marcus at A053767 CROSSREFS Intersection of A000217 and A053767. Cf. A066527, A154587, A294174. Sequence in context: A127536 A016201 A080618 * A082136 A153596 A316595 Adjacent sequences: A298267 A298268 A298269 * A298271 A298272 A298273 KEYWORD nonn AUTHOR Altug Alkan, Feb 15 2018 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified September 29 03:24 EDT 2023. Contains 365749 sequences. (Running on oeis4.)