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A347431
Antidiagonal sums of A047920.
2
1, 1, 2, 7, 29, 141, 832, 5729, 45217, 402359, 3985942, 43500339, 518515997, 6702036193, 93361811396, 1394334141349, 22223762217953, 376516856157771, 6756666799667818, 128025250352208551, 2554170591729180733, 53517087513085077221, 1174963644698963576488
OFFSET
0,3
LINKS
FORMULA
a(n) = Sum_{k=0..floor(n/2)} A047920(n-k,k).
a(n) mod 2 = A152822(n).
MAPLE
b:= proc(n, k) option remember;
`if`(k=0, n!, b(n, k-1)-b(n-1, k-1))
end:
a:= n-> add(b(n-k, k), k=0..n/2):
seq(a(n), n=0..23);
CROSSREFS
Sequence in context: A018977 A190736 A265000 * A355254 A030849 A185109
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Sep 01 2021
STATUS
approved