The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A113845 a(1) = a(2) = 1. a(n+1) = (Product_{k=1..floor(n/2)} a(k)) + (Product_{j=ceiling((n+1)/2)..n} a(j)). 0
 1, 1, 2, 3, 7, 43, 905, 817217, 222613996891, 49556991610450473684541, 350842202496894090472936261713260177362896247, 123090251052871637971528096077183553457511351225922468278558723122652153910477674845042677 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS a(13) has 177 digits. - Emeric Deutsch, Feb 06 2006 LINKS EXAMPLE (1*1*2) + (3*8*50*1202) = 1442402. a(8) = (a(1)*a(2)*a(3)) + (a(4)*a(5)*a(6)*a(7)) = (1*1*2) + (3*7*43*905) = 817217. MAPLE a[1]:=1: a[2]:=1: for n from 2 to 12 do a[n+1]:=product(a[k], k=1..floor(n/2))+product(a[j], j=1+floor(n/2)..n) od:seq(a[n], n=1..12); # Emeric Deutsch, Feb 06 2006 CROSSREFS Sequence in context: A072714 A051786 A133400 * A072713 A000058 A129871 Adjacent sequences:  A113842 A113843 A113844 * A113846 A113847 A113848 KEYWORD easy,nonn AUTHOR Leroy Quet, Jan 24 2006 EXTENSIONS Corrected and extended by Emeric Deutsch, Feb 06 2006 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 April 21 17:34 EDT 2021. Contains 343156 sequences. (Running on oeis4.)