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

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A225068 Least octagonal (8-gonal) number that is the product of n octagonal numbers greater than 1. 1
 8, 1408, 2165800, 37333296, 19384601600, 69370076160, 69370076160, 56288711711232000, 7917914554368000000, 199449790781142859776 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Lars Blomberg, Table of n, a(n) with solutions for n=1..10 EXAMPLE Let oct(n) = n*(3n-2). Then a(1) = 8 = oct(2). a(2) = 1408 = oct(22) = oct(2) * oct(8). a(3) = 2165800 = oct(850) = oct(4) * oct(5) * oct(17). a(4) = 37333296 = oct(3528) = oct(3)^2 * oct(8) * oct(13). a(5) = 19384601600 = oct(80384) = oct(2)^2 * oct(5) * oct(14) * oct(53). a(6) = 69370076160 = oct(152064) = oct(3)^3 * oct(4) * oct(7) * oct(22). CROSSREFS Cf. A000567 (octagonal numbers). Cf. A212616, A212617, A225066-A225070 (3-, 5- to 10-gonal cases). Sequence in context: A283902 A064073 A282889 * A270145 A201492 A172938 Adjacent sequences: A225065 A225066 A225067 * A225069 A225070 A225071 KEYWORD nonn,more AUTHOR T. D. Noe, May 01 2013 EXTENSIONS Corrected a(4) and added a(7)-a(10) by Lars Blomberg, Sep 21 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 | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified March 28 19:22 EDT 2023. Contains 361596 sequences. (Running on oeis4.)