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A182736
Sum of parts in all partitions of 2n that do not contain 1 as a part.
5
0, 2, 8, 24, 56, 120, 252, 476, 880, 1584, 2740, 4620, 7680, 12428, 19824, 31170, 48224, 73678, 111384, 166364, 246120, 360822, 524216, 755504, 1080912, 1535050, 2165592, 3036096, 4230632, 5861828, 8078820, 11076362, 15112384, 20523492, 27747128
OFFSET
0,2
COMMENTS
Essentially this is a bisection (even indices) of A138880.
LINKS
FORMULA
a(n) = 2*n*A182746(n). - Omar E. Pol, Dec 05 2010
MAPLE
b:= proc(n, i) option remember; local p, q;
if n<0 then [0, 0]
elif n=0 then [1, 0]
elif i<2 then [0, 0]
else p, q:= b(n, i-1), b(n-i, i);
[p[1]+q[1], p[2]+q[2]+q[1]*i]
fi
end:
a:= n-> b(2*n, 2*n)[2]:
seq(a(n), n=0..34); # Alois P. Heinz, Dec 03 2010
MATHEMATICA
b[n_] := (PartitionsP[n] - PartitionsP[n-1])*n; a[n_] := b[2n]; Table[a[n], {n, 0, 34}] (* Jean-François Alcover, Oct 07 2015 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Omar E. Pol, Dec 03 2010
EXTENSIONS
More terms from Alois P. Heinz, Dec 03 2010
STATUS
approved