%I A160181
%S A160181 1,1,2,3,7,18,59,221,936,4361,22083,120336,700653,4333933,28345090,
%T A160181 195233255,1411303635,10675375402,84276173439,692752181561,
%U A160181 5917018378496,52416910416933,480786834535250,4559132648864259
%N A160181 a(n) is the total number of partitions of sets containing from 0 to n
elements into blocks of at least 2 elements. It is the sum of the
first n+1 terms of A000296.
%C A160181 a(n) is the total number of complete rhyme schemes for 0 to n lines;
in other words, a(n) is the total number of rhyme schemes for 0 to
n lines where each line rhymes with at least one other line.
%C A160181 If the restriction that the blocks of the partitions must have at least
2 elements is removed, then A005001 is obtained except for the first
term of A005001.
%F A160181 See formulae for A000296.
%e A160181 a(7)=221 because the total number of partitions of sets containing from
0 to 7 elements into blocks of at least 2 elements is 221. The first
n+1=8 terms of A000296 are 1,0,1,1,4,11,41,162 and 1+0+1+1+4+11+41+162=221.
%Y A160181 Cf. A000296, A005001, A000110.
%Y A160181 Sequence in context: A005248 A032102 A100388 this_sequence A143874 A073641
A117763
%Y A160181 Adjacent sequences: A160178 A160179 A160180 this_sequence A160182 A160183
A160184
%K A160181 easy,nonn
%O A160181 0,3
%A A160181 Anonymous, May 03 2009
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