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A064173 Number of partitions of n with positive rank. +0
7
0, 1, 1, 2, 3, 5, 6, 10, 13, 19, 25, 35, 45, 62, 80, 106, 136, 178, 225, 291, 366, 466, 583, 735, 912, 1140, 1407, 1743, 2140, 2634, 3214, 3932, 4776, 5807, 7022, 8495, 10225, 12313, 14762, 17696, 21136, 25236, 30030, 35722, 42367, 50216, 59368, 70138 (list; graph; listen)
OFFSET

1,4

COMMENT

The rank of a partition is the largest summand minus the number of summands.

FORMULA

a(n) = (A000041(n)-A047993(n))/2.

a(n) = p(n-2)-p(n-7)+p(n-15)-... -(-1)^k*p(n-(3*k^2+k)/2)+..., where p() is A000041(). - Vladeta Jovovic (vladeta(AT)Eunet.yu), Aug 04 2004

EXAMPLE

a(20) = p(18)-p(13)+p(5) =385-101+7 = 291.

MAPLE

with(combinat): for n from 1 to 30 do P:=partition(n): c:=0: for j from 1 to nops(P) do if P[j][nops(P[j])]>nops(P[j]) then c:=c+1 else c:=c fi od: a[n]:=c: od: seq(a[n], n=1..30); - Emeric Deutsch (deutsch(AT)duke.poly.edu), Dec 11 2004

CROSSREFS

Cf. A063995.

Cf. A064174.

Sequence in context: A027339 A039837 A039838 this_sequence A039843 A045880 A014853

Adjacent sequences: A064170 A064171 A064172 this_sequence A064174 A064175 A064176

KEYWORD

nonn

AUTHOR

Vladeta Jovovic (vladeta(AT)Eunet.yu), Sep 19 2001

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Last modified September 5 01:44 EDT 2008. Contains 143476 sequences.


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