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!)
 A129913 a(n) is the number of ways of producing n, with an expression like: +- 1 # 2 # 3 # 4 # 5 # 6 # 7 # 8 # 9, where each # is replaced by any one of +,-,*,/; and the value is computed going left to right. 1

%I

%S 694,299,143,171,156,156,183,155,167,434,160,140,129,111,89,147,114,

%T 201,171,94,87,90,68,95,130,130,44,120,41,72,76,72,50,81,50,53,137,49,

%U 46,78,41,75,36,61,28,123,35,86,47,40,40,47,40,37,109,61,32,58,23,53

%N a(n) is the number of ways of producing n, with an expression like: +- 1 # 2 # 3 # 4 # 5 # 6 # 7 # 8 # 9, where each # is replaced by any one of +,-,*,/; and the value is computed going left to right.

%H Don Reble, <a href="/A129913/b129913.txt">Table of n, a(n) for n = 0..1000</a>

%H Don Reble, <a href="/A129913/a129913.txt">C++ program to compute sequence</a>

%e Going left-to-right, +1-2/3-4-5*6/7+8*9 = 0; and there are 694 such expressions which yield zero, so a(0)=694.

%K easy,nonn

%O 0,1

%A Jason Rodgers (Jason628(AT)gmail.com), Jun 05 2007, Jun 06 2007

%E Corrected and edited by _Don Reble_, Jun 23 2008

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 September 21 12:28 EDT 2021. Contains 347598 sequences. (Running on oeis4.)