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A016830
a(n) = (4*n+2)^6.
1
64, 46656, 1000000, 7529536, 34012224, 113379904, 308915776, 729000000, 1544804416, 3010936384, 5489031744, 9474296896, 15625000000, 24794911296, 38068692544, 56800235584, 82653950016, 117649000000, 164206490176, 225199600704, 304006671424, 404567235136, 531441000000
OFFSET
0,1
FORMULA
a(n) = 7*a(n-1) - 21*a(n-2) + 35*a(n-3) - 35*a(n-4) + 21*a(n-5) - 7*a(n-6) + a(n-7). - Harvey P. Dale, Oct 14 2012
From Amiram Eldar, Jul 07 2022: (Start)
a(n) = A016825(n)^6 = A016826(n)^3 = A016827(n)^2 = 64*A016758(n).
Sum_{n>=0} 1/a(n) = Pi^6/61440. (End)
MATHEMATICA
(4*Range[0, 20]+2)^6 (* or *) LinearRecurrence[{7, -21, 35, -35, 21, -7, 1}, {64, 46656, 1000000, 7529536, 34012224, 113379904, 308915776}, 20] (* Harvey P. Dale, Oct 14 2012 *)
CROSSREFS
KEYWORD
nonn,easy
STATUS
approved