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A101425
Number of different cuboids with volume p^5 X q^n, where p,q are distinct prime numbers.
4
5, 12, 24, 38, 57, 78, 104, 132, 165, 200, 240, 282, 329, 378, 432, 488, 549, 612, 680, 750, 825, 902, 984, 1068, 1157, 1248, 1344, 1442, 1545, 1650, 1760, 1872, 1989, 2108, 2232, 2358, 2489, 2622, 2760, 2900, 3045, 3192, 3344, 3498, 3657, 3818, 3984, 4152
OFFSET
0,1
COMMENTS
Subsequence of A034836, which gives the number of cuboids for volume n.
FORMULA
a(n) = A034836(2^5*3^n) = A034836(3^5*2^n) = A034836(p^5*q^n) for p,q distinct primes.
From Colin Barker, Mar 28 2014: (Start)
The following is conjectured.
a(n) = (37+3*(-1)^n+48*n+14*n^2)/8.
a(n) = 2*a(n-1)-2*a(n-3)+a(n-4).
G.f.: -(2*x+5)/((x+1)*(x-1)^3). (End)
CROSSREFS
KEYWORD
nonn
AUTHOR
Anthony C Robin, Jan 17 2005
EXTENSIONS
Edited and extended by Ray Chandler, Dec 19 2008
a(0)=5 prepended and g.f. edited by Alois P. Heinz, Oct 05 2016
STATUS
approved