A016821 a(n) = (4n+1)^9.

1, 1953125, 387420489, 10604499373, 118587876497, 794280046581, 3814697265625, 14507145975869, 46411484401953, 129961739795077, 327381934393961, 756680642578125, 1628413597910449, 3299763591802133, 6351461955384057, 11694146092834141, 20711912837890625, 35452087835576229

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• easy

Links

• Index entries for linear recurrences with constant coefficients, signature (10,-45,120,-210,252,-210,120,-45,10,-1).

Crossrefs

Cf. A013667, A016813.

Programs

Mathematica

Table[(4n+1)^9,{n,0,100}] (* Mohammad K. Azarian, Jun 20 2016 *)
LinearRecurrence[{10,-45,120,-210,252,-210,120,-45,10,-1},{1,1953125,387420489,10604499373,118587876497,794280046581,3814697265625,14507145975869,46411484401953,129961739795077},20] (* Harvey P. Dale, Sep 24 2022 *)

Formula

From Amiram Eldar, Apr 21 2023: (Start)

a(n) = A016813(n)^9.

Sum_{n>=0} 1/a(n) = 277*Pi^9/16515072 + 511*zeta(9)/1024. (End)