OFFSET
0,3
COMMENTS
Old name was: Row sums of A181842.
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..188 (terms n=1..80 from Vincenzo Librandi)
FORMULA
a(n) = Sum_{k>=0} k * A256067(n,k) = Sum_{k>=0} A256553(n,k)*A256554(n,k). - Alois P. Heinz, Apr 02 2015
MAPLE
with(combstruct):
a181844 := proc(n) local k, L, l, R, part;
R := NULL; L := 0;
for k from 1 to n do
part := iterstructs(Partition(n), size=k):
while not finished(part) do
l := nextstruct(part);
L := L + ilcm(op(l));
od;
od;
L end:
# second Maple program:
b:= proc(n, i, r) option remember; `if`(n=0, r, `if`(i<1, 0,
b(n, i-1, r)+b(n-i, min(i, n-i), ilcm(i, r))))
end:
a:= n-> b(n$2, 1):
seq(a(n), n=0..42); # Alois P. Heinz, Mar 18 2019
MATHEMATICA
t[n_, k_] := LCM @@@ IntegerPartitions[n, {n - k + 1}] // Total; a[n_] := Sum[t[n, k], {k, 1, n}]; Table[a[n], {n, 1, 32}] (* Jean-François Alcover, Jul 26 2013 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Peter Luschny, Dec 07 2010
EXTENSIONS
a(0)=1 prepended by Alois P. Heinz, Mar 29 2015
New name from Alois P. Heinz, Mar 18 2019
STATUS
approved