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A062810
a(n) = Sum_{i=1..n} i^(n - i) + (n - i)^i.
5
1, 3, 7, 17, 45, 131, 419, 1465, 5561, 22755, 99727, 465537, 2303829, 12037571, 66174411, 381560425, 2301307841, 14483421859, 94909491607, 646309392369, 4565559980989, 33401808977411, 252713264780595, 1974606909857945
OFFSET
1,2
LINKS
FORMULA
a(n) = 2 * A026898(n-1) - 1.
a(n) = 2 * A003101(n-1) + 1.
MATHEMATICA
Sum[i^(n - i) + (n - i)^i, {i, 1, n}]
PROG
(PARI) a(n) = sum(i=1, n, i^(n-i) + (n-i)^i); \\ Michel Marcus, Mar 24 2019
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Olivier Gérard, Jun 23 2001
STATUS
approved