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A067649
Numerators of power series for sqrt(1+x^2)/sqrt(1-x).
1
1, 1, 7, 9, 43, 87, 387, 665, 8499, 17003, 72345, 131903, 913919, 1825875, 7629371, 14275257, 410980675, 820899123, 3396389533, 6448133283, 47448015653, 94775447369, 389689995525, 746772134927, 11150225818167, 22273876637759
OFFSET
0,3
LINKS
MAPLE
S:= series(sqrt(1+x^2)/sqrt(1-x), x, 101):
seq(numer(coeff(S, x, j)), j=0..100); # Robert Israel, Apr 14 2021
CROSSREFS
Denominators are given in A046161(n)
Sequence in context: A323676 A007449 A189053 * A025631 A258183 A038275
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Feb 02 2002
STATUS
approved