

A053732


Number of ways to partition {1,...,n} into arithmetic progressions of length >= 1.


1



1, 2, 5, 13, 37, 111, 359, 1211, 4338, 16205, 63305, 254803, 1073370, 4638359, 20731961, 95072041, 449599410, 2170162939, 10782813595, 54579794359, 283240154578
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OFFSET

1,2


LINKS

Table of n, a(n) for n=1..21.


EXAMPLE

a(4) gives the total number of partitions of {1,2,3,4} (Bell(4); see A000110) excluding the partitions {1,2,4}{3} and {1,3,4}{2}. Hence a(4) = 15  2 = 13.


CROSSREFS

Cf. A000110.
Sequence in context: A003080 A149854 A151442 * A216617 A170941 A119495
Adjacent sequences: A053729 A053730 A053731 * A053733 A053734 A053735


KEYWORD

more,nonn,nice


AUTHOR

Marty Getz (ffmpg1(AT)uaf.edu) and Dixon Jones (fndjj(AT)uaf.edu), Feb 13 2000


EXTENSIONS

More terms from Winston C. Yang (winston(AT)cs.wisc.edu), May 20 2001
a(15)a(21) from Giovanni Resta, Feb 23 2009


STATUS

approved



