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A232863
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Numbers k such that (2*k-1)!! mod k! is greater than (2k+1)!! mod (k+1)!.
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0
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OFFSET
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1,1
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COMMENTS
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(2k-1)!! is the product of first k odd numbers.
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LINKS
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EXAMPLE
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MATHEMATICA
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o = 1; prev = cur = 0; Reap[For[n = 1, n < 3*10^6, n += 2, o *= n; prev = cur; cur = Mod[o, (Quotient[n, 2] + 1)!]; If[n > 1 && prev > cur, Print[(n - 1)/2]; Sow[(n - 1)/2]]]][[2, 1]] (* translated from Alex Ratushnyak's Python code *)
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PROG
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(Python)
o = f = 1
prev = 0
for n in range(1, 1000000):
o *= 2*n-1
f *= n
cur = o % f
if prev>cur: print str(n-1)+', ',
prev=cur
if (n&8191)==0: print '.',
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CROSSREFS
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KEYWORD
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nonn,hard,more
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AUTHOR
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STATUS
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approved
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