Re: A special kind of partitions of an integer
- To: mathgroup at smc.vnet.net
- Subject: [mg48125] Re: A special kind of partitions of an integer
- From: Cezar Augusto de Freitas Anselmo <cafa at ime.unicamp.br>
- Date: Fri, 14 May 2004 00:12:24 -0400 (EDT)
- References: <200405131305.JAA24791@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Dear friends, I'm looking in literature theory of certain partitions of a integer. Have you worked with partitions of a integer n in n terms where the summation is not associative (or know someone or texts about it, or other discussion list)? Example: I have to count P(n): the number of partitions of n with n positive integers (the only so integer is one) terms where the + operator is not associative, but is commutative; but the recurrence isn't simple. See below 2 = (1+1); (thus P(2)=1) 3 = ((1+1)+1); (thus P(3)=1) 4 = (((1+1)+1)+1), ((1+1)+(1+1)); (thus P(4)=2) = ((((1+1)+1)+1)+1), (((1+1)+(1+1))+1), (((1+1)+1)+(1+1)); (thus P(5)=3) P(6)=6 P(7)=11 Thanks for all help, -- ======================================== Cézar Freitas (ICQ 109128967) IMECC - UNICAMP / IME - USP Campinas / São Paulo, SP - Brasil