A089871
Least common multiple of all cycle sizes in range [A014137(n-1)..A014138(n-1)] of permutation A071663/A071664.
Original entry on oeis.org
1, 1, 2, 2, 2, 10, 40, 240, 5040, 388080, 5045040, 94643905622666400
Offset: 0
A089875
Least common multiple of all cycle sizes in range [A014137(n-1)..A014138(n-1)] of permutation A071665/A071666.
Original entry on oeis.org
1, 1, 1, 3, 3, 15, 30, 180, 3780, 291060, 3783780, 70982929216999800
Offset: 0
Original entry on oeis.org
1, 1, 0, 0, 0, 5, 0, 0, 0, 5, 0, 10, 0, 5, 0, 10, 0, 45, 0, 10, 0
Offset: 0
Original entry on oeis.org
1, 1, 2, 3, 6, 16, 36, 79, 162, 316, 604, 1204, 2244
Offset: 0
Original entry on oeis.org
1, 1, 1, 3, 3, 5, 11, 45, 257, 575, 2470, 10892, 30297
Offset: 0
A126319
Least common multiple of all cycle sizes in range [A014137(n-1)..A014138(n-1)] of permutation A125977/A125978.
Original entry on oeis.org
1, 1, 1, 3, 3, 15, 33, 9061920, 1252445414220, 126032376305404800, 50110448042127911907268800, 13399946812028296616282674883512406948355335893125182077721607466200299913000
Offset: 0
A126807
Numbers k such that A014138(k+1) (the partial sum of the first k Catalan numbers, starting 1, 2, 5, ...) is a prime.
Original entry on oeis.org
1, 8, 10, 30, 45, 145, 794, 2772, 2787, 9796, 38288, 39191, 40856, 41202, 47379
Offset: 1
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s[0]:=1: for n to 1000 do s[n]:= s[n-1]+binomial(2*n+2, n+1)/(n+2) end do: a:= proc (n) if isprime(s[n]) = true then n else end if end proc: seq(a(n), n= 0.. 1000); # Emeric Deutsch, Aug 28 2007
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s = 0; Do[s = s + (2n)!/n!/(n+1)!; If[ PrimeQ[s], Print[n-1]], {n, 200}]
Original entry on oeis.org
1, 1, 1, 3, 7, 10, 24, 39, 79, 148, 288, 528, 912
Offset: 0
Original entry on oeis.org
1, 1, 1, 2, 5, 8, 20, 30, 69, 116, 278, 416, 898
Offset: 0
Original entry on oeis.org
1, 1, 1, 2, 3, 6, 8, 8, 9, 10, 8, 14, 18, 10
Offset: 0
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