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A145227
a(n) = denominator of constant lambda(n) involved in a recurrence for the Atkin polynomials A_k(j).
1
1, 1, 1, 1, 5, 5, 1, 2, 6, 3, 11, 11, 13, 91, 35, 20, 68, 51, 57, 19, 1, 11, 253, 46, 50, 325, 117, 63, 203, 29, 31, 248, 88, 187, 85, 15, 111, 703, 247, 26, 82, 287, 301, 473, 165, 345, 1081, 188, 28, 35, 85, 221, 689, 477, 495, 770, 266, 551, 1711, 59, 61, 1891, 93, 48, 1040, 715
OFFSET
1,5
LINKS
M. Kaneko and D. Zagier, Supersingular j-invariants, hypergeometric series and Atkin's orthogonal polynomials, pp. 97-126 of D. A. Buell and J. T. Teitelbaum, eds., Computational Perspectives on Number Theory, Amer. Math. Soc., 1998
FORMULA
For formula see Maple code.
EXAMPLE
720, 546, 374, 475, 2001/5, 2294/5, 410, 903/2, 2491/6, 1342/3, 4602/11, 4891/11, ...
MAPLE
lambda:=proc(n) if n=1 then 720 else 12*(6+(-1)^n/(n-1))*(6+(-1)^n/n); fi; end;
CROSSREFS
Cf. A145226.
Sequence in context: A174119 A156696 A232651 * A236555 A282969 A046095
KEYWORD
nonn,frac
AUTHOR
N. J. A. Sloane, Feb 28 2009
STATUS
approved