A384893
Triangle read by rows where T(n,k) is the number of subsets of {1..n} with k maximal anti-runs (increasing by more than 1).
Original entry on oeis.org
1, 1, 1, 1, 2, 1, 1, 4, 2, 1, 1, 7, 5, 2, 1, 1, 12, 10, 6, 2, 1, 1, 20, 20, 13, 7, 2, 1, 1, 33, 38, 29, 16, 8, 2, 1, 1, 54, 71, 60, 39, 19, 9, 2, 1, 1, 88, 130, 122, 86, 50, 22, 10, 2, 1, 1, 143, 235, 241, 187, 116, 62, 25, 11, 2, 1, 1, 232, 420, 468, 392, 267, 150, 75, 28, 12, 2, 1
Offset: 0
The subset {3,6,7,9,11,12} has maximal anti-runs ((3,6),(7,9,11),(12)), so is counted under T(12,3).
The subset {3,6,7,9,10,12} has maximal anti-runs ((3,6),(7,9),(10,12)), so is counted under T(12,3).
Row n = 5 counts the following subsets:
{} {1} {1,2} {1,2,3} {1,2,3,4} {1,2,3,4,5}
{2} {2,3} {2,3,4} {2,3,4,5}
{3} {3,4} {3,4,5}
{4} {4,5} {1,2,3,5}
{5} {1,2,4} {1,2,4,5}
{1,3} {1,2,5} {1,3,4,5}
{1,4} {1,3,4}
{1,5} {1,4,5}
{2,4} {2,3,5}
{2,5} {2,4,5}
{3,5}
{1,3,5}
Triangle begins:
1
1 1
1 2 1
1 4 2 1
1 7 5 2 1
1 12 10 6 2 1
1 20 20 13 7 2 1
1 33 38 29 16 8 2 1
1 54 71 60 39 19 9 2 1
1 88 130 122 86 50 22 10 2 1
1 143 235 241 187 116 62 25 11 2 1
1 232 420 468 392 267 150 75 28 12 2 1
1 376 744 894 806 588 363 188 89 31 13 2 1
For runs instead of anti-runs we have
A034839, for strict partitions
A116674.
For integer partitions instead of subsets we have
A268193, strict
A384905.
A384175 counts subsets with all distinct lengths of maximal runs, complement
A384176.
A384877 gives lengths of maximal anti-runs in binary indices, firsts
A384878.
-
Table[Length[Select[Subsets[Range[n]],Length[Split[#,#2!=#1+1&]]==k&]],{n,0,10},{k,0,n}]
A204922
Ordered differences of Fibonacci numbers.
Original entry on oeis.org
1, 2, 1, 4, 3, 2, 7, 6, 5, 3, 12, 11, 10, 8, 5, 20, 19, 18, 16, 13, 8, 33, 32, 31, 29, 26, 21, 13, 54, 53, 52, 50, 47, 42, 34, 21, 88, 87, 86, 84, 81, 76, 68, 55, 34, 143, 142, 141, 139, 136, 131, 123, 110, 89, 55, 232, 231, 230, 228, 225, 220, 212, 199, 178
Offset: 1
a(1) = s(2) - s(1) = F(3) - F(2) = 2-1 = 1, where F=A000045;
a(2) = s(3) - s(1) = F(4) - F(2) = 3-1 = 2;
a(3) = s(3) - s(2) = F(4) - F(3) = 3-2 = 1;
a(4) = s(4) - s(1) = F(5) - F(2) = 5-1 = 4.
From _Emanuele Munarini_, Mar 29 2012: (Start)
Triangle begins:
1;
2, 1;
4, 3, 2;
7, 6, 5, 3;
12, 11, 10, 8, 5;
20, 19, 18, 16, 13, 8;
33, 32, 31, 29, 26, 21, 13;
54, 53, 52, 50, 47, 42, 34, 21;
88, 87, 86, 84, 81, 76, 68, 55, 34;
... (End)
-
/* As triangle */ [[Fibonacci(n+2)-Fibonacci(k+1) : k in [1..n]]: n in [1.. 15]]; // Vincenzo Librandi, Aug 04 2015
-
(See the program at A204924.)
-
create_list(fib(n+3)-fib(k+2),n,0,20,k,0,n); /* Emanuele Munarini, Mar 29 2012 */
-
{T(n,k) = fibonacci(n+2) - fibonacci(k+1)};
for(n=1,15, for(k=1,n, print1(T(n,k), ", "))) \\ G. C. Greubel, Feb 03 2019
-
[[fibonacci(n+2) - fibonacci(k+1) for k in (1..n)] for n in (1..15)] # G. C. Greubel, Feb 03 2019
A004070
Table of Whitney numbers W(n,k) read by antidiagonals, where W(n,k) is maximal number of pieces into which n-space is sliced by k hyperplanes, n >= 0, k >= 0.
Original entry on oeis.org
1, 1, 1, 1, 2, 1, 1, 2, 3, 1, 1, 2, 4, 4, 1, 1, 2, 4, 7, 5, 1, 1, 2, 4, 8, 11, 6, 1, 1, 2, 4, 8, 15, 16, 7, 1, 1, 2, 4, 8, 16, 26, 22, 8, 1, 1, 2, 4, 8, 16, 31, 42, 29, 9, 1, 1, 2, 4, 8, 16, 32, 57, 64, 37, 10, 1, 1, 2, 4, 8, 16, 32, 63, 99, 93, 46, 11, 1, 1, 2, 4, 8, 16, 32, 64, 120, 163
Offset: 0
Table W(n,k) begins:
1 1 1 1 1 1 1 ...
1 2 3 4 5 6 7 ...
1 2 4 7 11 16 22 ...
1 2 4 8 15 26 42 ...
W(2,4) = 11 because there are 11 length 4 binary sequences containing no more than 2 1's: {0, 0, 0, 0}, {0, 0, 0, 1}, {0, 0, 1, 0}, {0, 0, 1, 1}, {0, 1, 0, 0}, {0, 1, 0, 1}, {0, 1, 1, 0}, {1, 0, 0, 0}, {1, 0, 0, 1}, {1, 0, 1, 0}, {1, 1, 0, 0}. - _Geoffrey Critzer_, Mar 15 2010
Table T(n, k) begins:
1
1 1
1 2 1
1 2 3 1
1 2 4 4 1
1 2 4 7 5 1
1 2 4 8 11 6 1
...
- Donald E. Knuth, The Art of Computer Programming, Vol. 3, 2nd edition, Addison-Wesley, Reading, MA, 1998, p. 417.
- Gustav Burosch, Hans-Dietrich O.F. Gronau, Jean-Marie Laborde and Ingo Warnke, On posets of m-ary words, Discrete Math., Vol. 152, No. 1-3 (1996), pp. 69-91. MR1388633 (97e:06002)
- Matteo Cervetti and Luca Ferrari, Pattern avoidance in the matching pattern poset, arXiv:2009.01024 [math.CO], 2020.
- Matteo Cervetti and Luca Ferrari, Enumeration of Some Classes of Pattern Avoiding Matchings, with a Glimpse into the Matching Pattern Poset, Annals of Combinatorics (2022).
- Richard K. Guy, Letter to N. J. A. Sloane, Apr 1975.
- Yasuichi Horibe, An entropy view of Fibonacci trees, Fibonacci Quarterly, Vol. 20, No. 2 (1982), pp. 168-178.
- Robin Pemantle and Mark C. Wilson, Twenty Combinatorial Examples of Asymptotics Derived from Multivariate Generating Functions, SIAM Rev., Vol. 50, No. 2 (2008), pp. 199-272. See p. 233.
Rows are:
A000012,
A000027,
A000124,
A000125,
A000127,
A006261,
A008859,
A008860,
A008861,
A008862,
A008863.
-
Transpose[ Table[Table[Sum[Binomial[n, k], {k, 0, m}], {m, 0, 15}], {n, 0, 15}]] // Grid (* Geoffrey Critzer, Mar 15 2010 *)
T[ n_, k_] := Sum[ Binomial[n, j] (-1)^(n - j) Sum[ Binomial[j + k, i - k], {i, 0, j}], {j, 0, n}]; (* Michael Somos, May 31 2016 *)
-
/* array read by antidiagonals up coordinate index functions */
t1(n) = binomial(floor(3/2 + sqrt(2+2*n)), 2) - (n+1); /* A025581 */
t2(n) = n - binomial(floor(1/2 + sqrt(2+2*n)), 2); /* A002262 */
/* define the sequence array function for A004070 */
W(n, k) = sum(i=0, n, binomial(k, i));
/* visual check ( origin 0,0 ) */
printp(matrix(7, 7, n, k, W(n-1, k-1)));
/* print the sequence entries by antidiagonals going up ( origin 0,0 ) */
print1("S A004070 "); for(n=0, 32, print1(W(t1(n), t2(n))","));
print1("T A004070 "); for(n=33, 61, print1(W(t1(n), t2(n))","));
print1("U A004070 "); for(n=62, 86, print1(W(t1(n), t2(n))",")); /* Michael Somos, Apr 28 2000 */
-
T(n, k)=sum(m=0, n-k, binomial(k, m)) \\ Jianing Song, May 30 2022
More terms from Larry Reeves (larryr(AT)acm.org), Mar 20 2000
A048004
Triangular array read by rows: T(n,k) = number of binary vectors of length n whose longest run of consecutive 1's has length k, for n >= 0, 0 <= k <= n.
Original entry on oeis.org
1, 1, 1, 1, 2, 1, 1, 4, 2, 1, 1, 7, 5, 2, 1, 1, 12, 11, 5, 2, 1, 1, 20, 23, 12, 5, 2, 1, 1, 33, 47, 27, 12, 5, 2, 1, 1, 54, 94, 59, 28, 12, 5, 2, 1, 1, 88, 185, 127, 63, 28, 12, 5, 2, 1, 1, 143, 360, 269, 139, 64, 28, 12, 5, 2, 1, 1, 232, 694, 563, 303, 143, 64, 28, 12, 5, 2, 1, 1, 376, 1328, 1167, 653, 315, 144, 64, 28, 12, 5, 2, 1
Offset: 0
Triangle begins:
1;
1, 1;
1, 2, 1;
1, 4, 2, 1;
1, 7, 5, 2, 1;
1, 12, 11, 5, 2, 1;
1, 20, 23, 12, 5, 2, 1;
1, 33, 47, 27, 12, 5, 2, 1;
1, 54, 94, 59, 28, 12, 5, 2, 1;
1, 88, 185, 127, 63, 28, 12, 5, 2, 1;
...
Example: T(4,2) = 5 because we have 1100, 1101, 0110, 0011, 1011.
- J. Kappraff, Beyond Measure, World Scientific, 2002; see pp. 471-472.
- J. Riordan, An Introduction to Combinatorial Analysis, Wiley, 1958, p. 155.
T(n,2) = Fibonacci(n+2) - 1,
A000071, T(n,3) = b(n) for n=3, 4, ..., where b=
A000100, T(n,4) = c(n) for n = 4, 5, ..., where c=
A000102.
Nonnegative elements of columns approach
A045623.
-
tri n k | (k < 0) || (k > n) = 0
| (k == 0) || (k == n) = 1
| otherwise = 2*tri (n-1) k + tri (n-1) (k-1) - 2*tri (n-2) (k-1)
+ tri (n-k-1) (k-1) - tri (n-k-2) k
-- Valentin Hübner, Jul 20 2017, after David W. Wilson
-
G:=k->(1-x)^2*x^k/(1-2*x+x^(k+1))/(1-2*x+x^(k+2)): for k from 0 to 14 do g[k]:=series(G(k),x=0,15) od: 1,seq(seq(coeff(g[k],x^n),k=0..n),n=1..12); # Emeric Deutsch, Apr 01 2005
# second Maple program:
B:= proc(n, k) option remember; `if`(n=0 or k=1, 1,
add (B(n-j, k), j=1..min(n, k)))
end:
T:= (n, k)-> B(n+1, k+1)-B(n+1, k):
seq(seq(T(n, k), k=0..n), n=0..14); # Alois P. Heinz, May 21 2013
-
nn=10;f[list_]:=Select[list,#>0&];Map[f,Transpose[Table[ CoefficientList[ Series[(1-x^k)/(1-2x+x^(k+1))-(1-x^(k-1))/ (1-2x+x^k),{x,0,nn}],x],{k,1,nn}]]]//Grid (* Geoffrey Critzer, Jan 13 2013 *)
B[n_, k_] := B[n, k] = If[n==0 || k==1, 1, Sum[B[n-j, k], {j, 1, Min[n, k]} ]]; T[n_, k_] := B[n+1, k+1] - B[n+1, k]; Table[T[n, k], {n, 0, 14}, {k, 0, n}] // Flatten (* Jean-François Alcover, Dec 01 2015, after Alois P. Heinz *)
-
# See Richard Southern link.
-
# Computes the triangle obtained by augmenting T(n,k) by appending the column
# 1,0,0,0,... on the left. Illustrates a basic partition formula, is not
# efficient as a program for large n.
def A048004_row(n):
r = []
for k in (0..n):
s = 0
for p in Partitions(n, max_part=k, inner=[k]):
q = p.conjugate()
s += mul(binomial(q[j],q[j+1]) for j in range(len(q)-1))
r.append(s)
return r
[A048004_row(n) for n in (0..9)] # Peter Luschny, Jul 13 2015
A052509
Knights-move Pascal triangle: T(n,k), n >= 0, 0 <= k <= n; T(n,0) = T(n,n) = 1, T(n,k) = T(n-1,k) + T(n-2,k-1) for k = 1,2,...,n-1, n >= 2.
Original entry on oeis.org
1, 1, 1, 1, 2, 1, 1, 3, 2, 1, 1, 4, 4, 2, 1, 1, 5, 7, 4, 2, 1, 1, 6, 11, 8, 4, 2, 1, 1, 7, 16, 15, 8, 4, 2, 1, 1, 8, 22, 26, 16, 8, 4, 2, 1, 1, 9, 29, 42, 31, 16, 8, 4, 2, 1, 1, 10, 37, 64, 57, 32, 16, 8, 4, 2, 1, 1, 11, 46, 93, 99, 63, 32, 16, 8, 4, 2, 1
Offset: 0
Triangle begins:
[0] 1;
[1] 1, 1;
[2] 1, 2, 1;
[3] 1, 3, 2, 1;
[4] 1, 4, 4, 2, 1;
[5] 1, 5, 7, 4, 2, 1;
[6] 1, 6, 11, 8, 4, 2, 1;
[7] 1, 7, 16, 15, 8, 4, 2, 1;
[8] 1, 8, 22, 26, 16, 8, 4, 2, 1;
[9] 1, 9, 29, 42, 31, 16, 8, 4, 2, 1;
As a square array, this begins:
1 1 1 1 1 1 ...
1 2 2 2 2 2 ...
1 3 4 4 4 4 ...
1 4 7 8 8 8 ...
1 5 11 15 16 ...
1 6 16 26 31 32 ...
- Reinhard Zumkeller, Rows n = 0..150 of triangle, flattened
- Clark Kimberling, Path-counting and Fibonacci numbers, Fib. Quart. 40 (4) (2002) 328-338, Example 1C.
- Daniel Q. Naiman and Edward R. Scheinerman, Arbitrage and Geometry, arXiv:1709.07446 [q-fin.MF], 2017 [Contains the square array multiplied by 2].
- Richard L. Ollerton and Anthony G. Shannon, Some properties of generalized Pascal squares and triangles, Fib. Q., 36 (1998), 98-109. See Tables 5 and 14.
- D. J. Price, Some unusual series occurring in n-dimensional geometry, Math. Gaz., 30 (1946), 149-150.
- Index entries for triangles and arrays related to Pascal's triangle
Partial sums across rows of (extended) Pascal's triangle
A052553.
-
A052509:=Flat(List([0..100],n->List([0..n],k->Sum([0..n],m->Binomial(n-k,k-m))))); # Muniru A Asiru, Sat Feb 17 2018
-
a052509 n k = a052509_tabl !! n !! k
a052509_row n = a052509_tabl !! n
a052509_tabl = [1] : [1,1] : f [1] [1,1] where
f row' row = rs : f row rs where
rs = zipWith (+) ([0] ++ row' ++ [1]) (row ++ [0])
-- Reinhard Zumkeller, Nov 22 2012
-
[[(&+[Binomial(n-k, k-j): j in [0..n]]): k in [0..n]]: n in [0..10]]; // G. C. Greubel, May 13 2019
-
a := proc(n::nonnegint, k::nonnegint) option remember: if k=0 then RETURN(1) fi: if k=n then RETURN(1) fi: a(n-1,k)+a(n-2,k-1) end: for n from 0 to 11 do for k from 0 to n do printf(`%d,`,a(n,k)) od: od: # James Sellers, Mar 17 2000
with(combinat): for s from 0 to 11 do for n from s to 0 by -1 do if n=0 or s-n=0 then printf(`%d,`,1) else printf(`%d,`,sum(binomial(n, i), i=0..s-n)) fi; od: od: # James Sellers, Mar 17 2000
-
Table[Sum[Binomial[n-k, k-m], {m, 0, n}], {n, 0, 10}, {k, 0, n}]
T[n_, k_] := Hypergeometric2F1[-k, -n + k, -k, -1];
Table[T[n, k], {n, 0, 10}, {k, 0, n}] // Flatten (* Peter Luschny, Nov 28 2021 *)
-
T(n,k)=sum(m=0,n,binomial(n-k,k-m));
for(n=0,10,for(k=0,n,print1(T(n,k),", "););print();); /* show triangle */
-
[[sum(binomial(n-k, k-j) for j in (0..n)) for k in (0..n)] for n in (0..10)] # G. C. Greubel, May 13 2019
Entry formed by merging two earlier entries. -
N. J. A. Sloane, Jun 17 2007
A140993
Triangle G(n, k) read by rows, for 1 <= k <= n, where G(n, n) = G(n+1, 1) = 1, G(n+2, 2) = 2, G(n+3, m) = G(n+1, m-1) + G(n+1, m-2) + G(n+2, m-1) for n >= 1 and m = 3..(n+2).
Original entry on oeis.org
1, 1, 1, 1, 2, 1, 1, 2, 4, 1, 1, 2, 5, 7, 1, 1, 2, 5, 11, 12, 1, 1, 2, 5, 12, 23, 20, 1, 1, 2, 5, 12, 28, 46, 33, 1, 1, 2, 5, 12, 29, 63, 89, 54, 1, 1, 2, 5, 12, 29, 69, 137, 168, 88, 1, 1, 2, 5, 12, 29, 70, 161, 289, 311, 143, 1, 1, 2, 5, 12, 29, 70, 168, 367, 594, 567, 232, 1, 1, 2, 5, 12, 29, 70, 169, 399, 817, 1194, 1021, 376, 1
Offset: 1
Triangle G(n,k) (with rows for n >= 1 and columns for 1 <= k <= n) begins:
1
1 1
1 2 1
1 2 4 1
1 2 5 7 1
1 2 5 11 12 1
1 2 5 12 23 20 1
1 2 5 12 28 46 33 1
1 2 5 12 29 63 89 54 1
1 2 5 12 29 69 137 168 88 1
1 2 5 12 29 70 161 289 311 143 1
1 2 5 12 29 70 168 367 594 567 232 1
1 2 5 12 29 70 169 399 817 1194 1021 376 1
1 2 5 12 29 70 169 407 934 1778 2355 1820 609 1
...
From _Petros Hadjicostas_, Feb 09 2021: (Start)
Rectangular array RA(n,k) (with rows for n >= 1 and columns for k >= 1) begins:
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, ...
1, 2, 4, 7, 12, 20, 33, 54, 88, 143, ...
1, 2, 5, 11, 23, 46, 89, 168, 311, 567, ...
1, 2, 5, 12, 28, 63, 137, 289, 594, 1194, ...
1, 2, 5, 12, 29, 69, 161, 367, 817, 1778, ...
1, 2, 5, 12, 29, 70, 168, 399, 934, 2150, ...
1, 2, 5, 12, 29, 70, 169, 407, 975, 2316, ...
1, 2, 5, 12, 29, 70, 169, 408, 984, 2367, ...
1, 2, 5, 12, 29, 70, 169, 408, 985, 2377, ...
1, 2, 5, 12, 29, 70, 169, 408, 985, 2378, ...
...
Reading the array RA(n,k) by ascending antidiagonals, we get triangle G(n,k) above. (End)
Cf.
A000071,
A000079,
A000129,
A007318,
A140994,
A140995,
A140996,
A140997,
A140998,
A141020,
A141021.
-
A140993 := proc(n,k) if k = n then 1; elif k = 1 then 1; elif k = 2 then 2; else procname(n-2,k-1)+procname(n-2,k-2)+procname(n-1,k-1) ; end if; end proc: seq(seq(A140993(n,k),k=1..n),n=1..15) ; # R. J. Mathar, Apr 28 2010
-
t[n_, k_] := If[k == n, 1, If[k == 1, 1, If[k == 2, 2, t[n - 2, k - 1] + t[n - 2, k - 2] + t[n - 1, k - 1]]]]; Flatten[Table[ t[n, k], {n, 13}, {k, n}]] (* Robert G. Wilson v, Dec 22 2011 *)
A140998
Triangle G(n, k), read by rows, for 0 <= k <= n, where G(n, 0) = G(n+1, n+1) = 1, G(n+2, n+1) = 2, and G(n+3, m) = G(n+1, m-1) + G(n+1, m) + G(n+2, m) for n >= 0 and m = 1..n+1.
Original entry on oeis.org
1, 1, 1, 1, 2, 1, 1, 4, 2, 1, 1, 7, 5, 2, 1, 1, 12, 11, 5, 2, 1, 1, 20, 23, 12, 5, 2, 1, 1, 33, 46, 28, 12, 5, 2, 1, 1, 54, 89, 63, 29, 12, 5, 2, 1, 1, 88, 168, 137, 69, 29, 12, 5, 2, 1, 1, 143, 311, 289, 161, 70, 29, 12, 5, 2, 1, 1, 232, 567, 594, 367, 168, 70, 29, 12, 5, 2, 1
Offset: 0
Triangle begins (with rows for n >= 0 and columns for k >= 0):
1;
1, 1;
1, 2, 1;
1, 4, 2, 1;
1, 7, 5, 2, 1;
1, 12, 11, 5, 2, 1;
1, 20, 23, 12, 5, 2, 1;
1, 33, 46, 28, 12, 5, 2, 1;
1, 54, 89, 63, 29, 12, 5, 2, 1;
1, 88, 168, 137, 69, 29, 12, 5, 2, 1;
1, 143, 311, 289, 161, 70, 29, 12, 5, 2, 1;
-
G[n_,k_] := G[n,k] = Which[k==0 || k==n, 1, k==n-1, 2, True, G[n-2,k-1] + G[n-2,k] + G[n-1,k]]; Table[G[n,k], {n,0,12}, {k,0,n}] (* Jean-François Alcover, Jun 09 2019 *)
-
G(n,k) = if(k==0 || k==n, 1, if(k==n-1, 2, G(n-1, k) + G(n-2, k) + G(n-2, k-1)));
for(n=0,12, for(k=0,n, print1(G(n,k), ", "))) \\ G. C. Greubel, Jun 09 2019
-
def G(n,k):
if (k==0 or k==n): return 1
elif (k==n-1): return 2
else: return G(n-1, k) + G(n-2, k) + G(n-2, k-1)
[[G(n,k) for k in (0..n)] for n in (0..12)] # G. C. Greubel, Jun 09 2019
Indices in the definition corrected by
R. J. Mathar, Aug 02 2009
A006327
a(n) = Fibonacci(n) - 3. Number of total preorders.
Original entry on oeis.org
0, 2, 5, 10, 18, 31, 52, 86, 141, 230, 374, 607, 984, 1594, 2581, 4178, 6762, 10943, 17708, 28654, 46365, 75022, 121390, 196415, 317808, 514226, 832037, 1346266, 2178306, 3524575, 5702884, 9227462, 14930349, 24157814, 39088166, 63245983, 102334152, 165580138
Offset: 4
G.f. = 2*x^5 + 5*x^6 + 10*x^7 + 18*x^8 + 31*x^9 + 52*x^10 + 86*x^11 + ...
- N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
- T. D. Noe, Table of n, a(n) for n = 4..1000
- G. Kreweras, Les préordres totaux compatibles avec un ordre partiel, Math. Sci. Humaines No. 53 (1976), 5-30.
- G. Kreweras, Les préordres totaux compatibles avec un ordre partiel, Math. Sci. Humaines No. 53 (1976), 5-30. (Annotated scanned copy)
- Simon Plouffe, Approximations de séries génératrices et quelques conjectures, Dissertation, Université du Québec à Montréal, 1992; arXiv:0911.4975 [math.NT], 2009.
- Simon Plouffe, 1031 Generating Functions, Appendix to Thesis, Montreal, 1992
- A. Sapounakis, I. Tasoulas and P. Tsikouras, On the Dominance Partial Ordering of Dyck Paths, Journal of Integer Sequences, Vol. 9 (2006), Article 06.2.5.
- A. B. Vinokur, Huffman trees and Fibonacci numbers, Kibernetika Issue 6 (1986) 9-12 (in Russian); English translation in Cybernetics 21, Issue 6 (1986), 692-696.
- Alex Vinokur, Fibonacci connection between Huffman codes and Wythoff array, arXiv:cs/0410013 [cs.DM], 2004-2005.
- Index entries for linear recurrences with constant coefficients, signature (2,0,-1).
Cf.
A000045,
A001611,
A000071,
A157725,
A001911,
A157726,
A006327,
A157727,
A157728,
A157729,
A167616. [Added by
N. J. A. Sloane, Jun 25 2010 in response to a comment from
Aviezri S. Fraenkel]
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List([4..45], n-> Fibonacci(n)-3) # G. C. Greubel, Jul 13 2019
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[Fibonacci(n)-3: n in [4..45]]; // G. C. Greubel, Jul 13 2019
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with(combinat):a:=n->sum(fibonacci(j),j=3..n): seq(a(n),n=2..40); # Zerinvary Lajos, Oct 03 2007
A006327:=(2+z)/(z-1)/(z**2+z-1); # conjectured by Simon Plouffe in his 1992 dissertation
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Fibonacci[Range[4, 45]] - 3 (* Vladimir Joseph Stephan Orlovsky, Mar 19 2010 *)
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a(n)=fibonacci(n)-3 \\ Charles R Greathouse IV, Feb 03 2014
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[fibonacci(n)-3 for n in (4..45)] # G. C. Greubel, Jul 13 2019
A056830
Alternate digits 1 and 0.
Original entry on oeis.org
0, 1, 10, 101, 1010, 10101, 101010, 1010101, 10101010, 101010101, 1010101010, 10101010101, 101010101010, 1010101010101, 10101010101010, 101010101010101, 1010101010101010, 10101010101010101, 101010101010101010
Offset: 0
n a(n) A000975(n) (If a(n) is interpreted in base 2.)
------------------------------
0 0 ....................... 0
1 1 ....................... 1
2 10 ...................... 2 = 2^1
3 101 ..................... 5
4 1010 ................... 10 = 2^1 + 2^3
5 10101 .................. 21
6 101010 ................. 42 = 2^1 + 2^3 + 2^5
7 1010101 ................ 85
8 10101010 .............. 170 = 2^1 + 2^3 + 2^5 + 2^7
9 101010101 ............. 341
10 1010101010 ............ 682 = 2^1 + 2^3 + 2^5 + 2^7 + 2^9
11 10101010101 .......... 1365
12 101010101010 ......... 2730 = 2^1 + 2^3 + 2^5 + 2^7 + 2^9 + 2^11, etc.
- _Bruno Berselli_, Dec 02 2015
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List([0..30], n-> Int(10^(n+1)/99) ); # G. C. Greubel, Jul 14 2019
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[Round((20*10^n-11)/198) : n in [0..30]]; // Vincenzo Librandi, Jun 25 2011
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A056830 := proc(n) floor(10^(n+1)/99) ; end proc:
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CoefficientList[Series[x/((1-x^2)*(1-10*x)), {x,0,30}], x] (* G. C. Greubel, Sep 26 2017 *)
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Vec(x/((1-x)*(1+x)*(1-10*x))+O(x^30)) \\ Charles R Greathouse IV, Feb 13 2017
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[floor(10^(n+1)/99) for n in (0..30)] # G. C. Greubel, Jul 14 2019
A083047
Square table read by antidiagonals forms a permutation of the natural numbers: T(n,0) = floor(n*x/(x-1))+1, T(n,k+1) = ceiling(x*T(n,k)), where x = (sqrt(5)+1)/2, n>=0, k>=0.
Original entry on oeis.org
1, 2, 3, 4, 5, 6, 7, 9, 10, 8, 12, 15, 17, 13, 11, 20, 25, 28, 22, 18, 14, 33, 41, 46, 36, 30, 23, 16, 54, 67, 75, 59, 49, 38, 26, 19, 88, 109, 122, 96, 80, 62, 43, 31, 21, 143, 177, 198, 156, 130, 101, 70, 51, 34, 24, 232, 287, 321, 253, 211, 164, 114, 83, 56, 39, 27, 376
Offset: 0
Table begins:
1 2 4 7 12 20 33 54 88 143 232 376 ...
3 5 9 15 25 41 67 109 177 287 465 753 ...
6 10 17 28 46 75 122 198 321 520 842 1363 ...
8 13 22 36 59 96 156 253 410 664 1075 1740 ...
11 18 30 49 80 130 211 342 554 897 1452 2350 ...
14 23 38 62 101 164 266 431 698 1130 1829 2960 ...
16 26 43 70 114 185 300 486 787 1274 2062 3337 ...
19 31 51 83 135 219 355 575 931 1507 2439 3947 ...
21 34 56 91 148 240 389 630 1020 1651 2672 4324 ...
24 39 64 104 169 274 444 719 1164 1884 3049 4934 ...
27 44 72 117 190 308 499 808 1308 2117 3426 5544 ...
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t[n_, 0] = Floor[n*GoldenRatio/(GoldenRatio - 1) + 1];
t[n_, k_] := t[n, k] = Ceiling[GoldenRatio*t[n, k-1]];
Flatten[Table[t[k-1, n-k ], {n, 12}, {k, n}] ][[;; 67]]
(* Jean-François Alcover, Jul 13 2011 *)
Comments