%I A096825
%S A096825 1,1,1,1,1,2,1,1,1,2,1,2,1,2,2,1,1,2,1,2,2,2,1,2,1,2,1,2,1,3,1,1,2,2,2,
%T A096825 3,1,2,2,2,1,3,1,2,2,2,1,2,1,2,2,2,1,2,2,2,2,2,1,4,1,2,2,1,2,3,1,2,2,3,
%U A096825 1,3,1,2,2,2,2,3,1,2,1,2,1,4,2,2,2,2,1,4,2,2,2,2,2,2,1,2,2,3
%N A096825 Maximal size of an antichain in divisor lattice D(n).
%C A096825 The divisor lattice D(n) is the lattice of the divisors of the natural
number n.
%F A096825 a(n) is the coefficient at x^k in (1+x+...+x^k_1)*...*(1+x+...+x^k_q)
where n=p_1^k_1*...*p_q^k_q is the prime factorization of n and k=floor((k_1+...+k_q)/
2). - Alec Mihailovs (alec(AT)mihailovs.com), Aug 22 2004
%p A096825 a:=proc(n) local klist,x; klist:=ifactors(n)[2,1..-1,2]; coeff(normal(mul((1-x^(k+1))/
(1-x),k=klist)),x,floor(add(k,k=klist)/2)) end: seq(a(n), n=1..100);
%Y A096825 Cf. A096826, A096827.
%Y A096825 Sequence in context: A079553 A001221 A064372 this_sequence A007875 A050320
A121382
%Y A096825 Adjacent sequences: A096822 A096823 A096824 this_sequence A096826 A096827
A096828
%K A096825 nonn
%O A096825 1,6
%A A096825 Yuval Dekel (dekelyuval(AT)hotmail.com) and Vladeta Jovovic (vladeta(AT)eunet.rs),
Aug 17 2004
%E A096825 More terms from Alec Mihailovs (alec(AT)mihailovs.com), Aug 22 2004
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