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A232620
Numbers n such that (2n)!! mod (2n-1)!! is greater than (2n+2)!! mod (2n+1)!!.
1
4, 615, 9090, 11011
OFFSET
1,1
COMMENTS
Numbers n such that A232618(n) > A232618(n+1).
a(5) > 10 * 2^20.
EXAMPLE
4 is in the sequence because A232618(4) > A232618(5).
PROG
(Python)
o=e=1 # odd, even
prev=0
for n in range(1, 1000000000, 2):
o*=n
e*=n+1
cur = e%o
if prev>cur: print(str(n//2), end=', ')
prev=cur
CROSSREFS
Sequence in context: A069641 A215920 A210853 * A219892 A079103 A191953
KEYWORD
nonn,hard,more
AUTHOR
Alex Ratushnyak, Nov 27 2013
STATUS
approved