A089408
Number of fixed points in range [A014137(n-1)..A014138(n-1)] of permutation A089864.
Original entry on oeis.org
1, 1, 2, 1, 2, 2, 4, 5, 10, 14, 28, 42, 84, 132, 264, 429, 858, 1430, 2860, 4862, 9724, 16796, 33592, 58786, 117572, 208012, 416024, 742900, 1485800, 2674440, 5348880, 9694845, 19389690, 35357670, 70715340, 129644790, 259289580, 477638700
Offset: 0
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seq(seq(binomial(2*j,j)/(1+j)*i, i=1..2),j=0..19); # Zerinvary Lajos, Apr 29 2007
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a[0] = 1; a[n_] := If[EvenQ[n], 2*CatalanNumber[n/2 - 1], CatalanNumber[(n-1)/2]]; Table[a[n], {n, 0, 40}] (* Jean-François Alcover, Jul 24 2013 *)
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from sympy import catalan
def a(n): return 1 if n==0 else 2*catalan(n//2 - 1) if n%2==0 else catalan((n - 1)//2) # Indranil Ghosh, May 23 2017
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(define (A089408 n) (cond ((zero? n) 1) ((even? n) (* 2 (A000108 (-1+ (/ n 2))))) (else (A000108 (/ (-1+ n) 2)))))
Original entry on oeis.org
1, 1, 1, 2, 3, 10, 18, 46, 95, 236, 528, 1288, 2936, 6984, 16212, 38528, 90717, 216648, 516358, 1240818, 2979992
Offset: 0
Occurs for first time in
A073201 as row 2614.
Original entry on oeis.org
1, 1, 2, 3, 6, 6, 24, 72, 144, 147, 588, 672, 2136, 10152, 11520, 29484, 117936, 270576, 656352, 2062368, 4040160
Offset: 0
Occurs for first time in
A073203 as row 2614.
A060114
Least common multiple of all cycle sizes in range [A014137(n-1)..A014138(n-1)] of permutation A057505/A057506.
Original entry on oeis.org
1, 1, 2, 6, 6, 30, 120, 720, 15120, 1164240, 15135120, 283931716867999200, 14510088480716327580681600, 3280681990411073806237542217555200, 936436634805345771521186435213604447980767985241556128000
Offset: 0
Occurs for first time in
A073204 as row 2614.
Original entry on oeis.org
0, 1, 2, 2, 4, 4, 4, 4, 4, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65
Offset: 0
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a014137[n_] := Sum[CatalanNumber[k], {k, 0, n}];
a072643[n_] := Module[{i, c, a}, i = c = 0; a = 1; While[n > c, a *= (4*i + 2)/(i + 2); i++; c += a]; i];
a[n_] := a014137[a072643[n] - 1];
Table[a[n], {n, 0, 76}] (* Jean-François Alcover, Dec 26 2017 *)
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def A082852(n) :
i = c = 0; a = 1
while n > c :
a *= (4*i+2)/(2+i)
i += 1; c += a
return c-a+1
[A082852(n) for n in (0..76)] # - Peter Luschny, Sep 07 2012
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(define (A082852 n) (if (zero? n) 0 (A014137 (-1+ (A072643 n)))))
Original entry on oeis.org
1, 1, 2, 5, 9, 28, 57, 253, 842, 3753, 10927, 15014, 130831, 218961, 967104, 3767216, 29715310, 89923607, 314897868, 785059994
Offset: 0
A073191
Number of separate orbits/cycles to which the Catalan bijections A072796/A072797 partition each A000108(n) structures encoded in the range [A014137(n-1)..A014138(n-1)] of the sequence A014486/A063171.
Original entry on oeis.org
1, 1, 2, 4, 11, 31, 96, 305, 1007, 3389, 11636, 40498, 142714, 507870, 1823040, 6591885, 23989419, 87795473, 322922652, 1193058230, 4425547638, 16475756738, 61539293424, 230548633954, 866095934598, 3261868457698, 12313423931624
Offset: 0
Occurs for first time in
A073201 as row 1.
A073193
Number of separate orbits/cycles to which the Catalan bijection A057508 partitions each A000108(n) structures encoded in the range [A014137(n-1)..A014138(n-1)] of the sequence A014486/A063171.
Original entry on oeis.org
1, 1, 2, 4, 11, 30, 93, 292, 965, 3238, 11126, 38708, 136486, 485820, 1744677, 6310584, 22973793, 84103302, 309429066, 1143487428, 4242631626, 15798011604, 59018856522, 221143860936, 830895360978, 3129747395548, 11816242209260
Offset: 0
Occurs for first time in
A073201 as row 168.
A073431
Number of separate orbits/cycles to which the Catalan bijections A069767/A069768 partition each A000108(n) structures encoded in the range [A014137(n-1)..A014138(n-1)] of the sequence A014486/A063171.
Original entry on oeis.org
1, 1, 1, 2, 3, 6, 12, 28, 65, 160, 408, 1074, 2898, 7998, 22508, 64426, 187251, 551730, 1645840, 4964876, 15130808, 46545788, 144424944, 451715460
Offset: 0
Occurs for first time in
A073201 as row 6 (and 8). Column sums of the square array
A074079/Row sums of the triangle
A074080.
A074080
Triangle T(n,k) (listed in order T(1,0), T(2,0), T(2,1), T(3,0), T(3,1), T(3,2), T(4,0), etc.) giving the number of 2^k-cycles that occur in the n-th sub-permutation of A069767/A069768 (i.e., in the range [A014137(n-1)..A014138(n-1)] inclusive).
Original entry on oeis.org
1, 0, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 2, 2, 1, 0, 0, 3, 5, 3, 1, 1, 0, 3, 10, 9, 4, 1, 0, 1, 3, 17, 24, 14, 5, 1, 0, 1, 3, 28, 57, 44, 20, 6, 1, 0, 0, 5, 41, 128, 128, 71, 27, 7, 1, 0, 1, 4, 60, 271, 354, 234, 106, 35, 8, 1, 0, 0, 5, 81, 549, 937, 738, 384, 150, 44, 9, 1, 0, 0, 5, 106, 1061
Offset: 0
If we take the fifth such sub-permutation, i.e., the subsequence A069767[23..64]: [45,46,48,49,50,54,55,57,58,59,61,62,63,64,44,47,53,56,60,43,52,40,31,32,41,34,35,36,42,51,39,30,33,38,29,26,27,37,28,25,24,23], subtract 22 from each term and convert the resulting permutation of [1..42] to disjoint cycle notation, we get:
(17,31),(20,21,30,29),(3,26,12,40),(6,32,8,35,7,33,11,39),(15,22,18,34,16,25,19,38),(1,23,9,36,4,27,13,41,2,24,10,37,5,28,14,42)
which implies that T(5,0) = 0 (no fixed elements), T(5,1) = 1 (one transposition), T(5,2) = 2 (two 4-cycles), T(5,3) = 2 (two 8-cycles), T(5,4) = 1 (and one 16-cycle). It is guaranteed that only cycles whose length is a power of 2 occur in A069767/A069768.
Upper triangular region of the square array
A074079 (actually, only the area above its main diagonal, excluding also the leftmost column). T(n, k) =
A073430(n, k)/(2^k) [with the rightmost edge of
A073430 discarded]. Row sums:
A073431.
A000108(n) = Sum_{i=0..n-1} 2^i * T(n, i). Cf.
A073346,
A003056,
A002262.
Showing 1-10 of 313 results.
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