A187760 -id:A187760 - cp's OEIS frontend

A004738 Concatenation of sequences (1,2,...,n-1,n,n-1,...,2) for n >= 2.

1, 2, 1, 2, 3, 2, 1, 2, 3, 4, 3, 2, 1, 2, 3, 4, 5, 4, 3, 2, 1, 2, 3, 4, 5, 6, 5, 4, 3, 2, 1, 2, 3, 4, 5, 6, 7, 6, 5, 4, 3, 2, 1, 2, 3, 4, 5, 6, 7, 8, 7, 6, 5, 4, 3, 2, 1, 2, 3, 4, 5, 6, 7, 8, 9, 8, 7, 6, 5, 4, 3, 2, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 10, 9

Offset: 1

R. Muller

Also concatenation of sequences n,n-1,...,2,1,2,...,n-1,n.

Table T(n,k) n, k > 0, T(n,k) = n-k+1, if n >= k, T(n,k) = k-n+1, if n < k. Table read by sides of squares from T(1,n) to T(n,n), then from T(n,n) to T(n,1). General case A209301. Let m be a natural number. The first column of the table T(n,1) is the sequence of the natural numbers A000027. In all columns with number k (k > 1) the segment with the length of (k-1): {m+k-2, m+k-3, ..., m} shifts the sequence A000027. For m=1 the result is A004739, for m=2 the result is A004738, for m=3 the result is A209301. - Boris Putievskiy, Jan 24 2013

			From _Boris Putievskiy_, Jan 24 2013: (Start)
The start of the sequence as table:
  1, 2, 3, 4, 5, 6, 7, ...
  2, 1, 2, 3, 4, 5, 6, ...
  3, 2, 1, 2, 3, 4, 5, ...
  4, 3, 2, 1, 2, 3, 4, ...
  5, 4, 3, 2, 1, 2, 3, ...
  6, 5, 4, 3, 2, 1, 2, ...
  7, 6, 5, 4, 3, 2, 1, ...
  ...
The start of the sequence as triangle array read by rows:
  1;
  2, 1, 2;
  3, 2, 1, 2, 3;
  4, 3, 2, 1, 2, 3, 4;
  5, 4, 3, 2, 1, 2, 3, 4, 5;
  6, 5, 4, 3, 2, 1, 2, 3, 4, 5, 6;
  7, 6, 5, 4, 3, 2, 1, 2, 3, 4, 5, 6, 7;
  ...
Row number r contains 2*r - 1 numbers: r, r-1, ..., 1, 2, ..., r. (End)

F. Smarandache, "Numerical Sequences", University of Craiova, 1975; [ See Arizona State University, Special Collection, Tempe, AZ, USA ].

Boris Putievskiy, Transformations [Of] Integer Sequences And Pairing Functions, arXiv preprint arXiv:1212.2732 [math.CO], 2012.
F. Smarandache, Collected Papers, Vol. II
F. Smarandache, Sequences of Numbers Involved in Unsolved Problems.
Eric Weisstein's World of Mathematics, Smarandache Sequences

Cf. A004737, A004739, A187760, A079813, A209301.

A004738 := proc(n)
    local tri ;
    tri := floor(sqrt(n)+1/2) ;
    tri+1-abs(n-1-tri^2) ;
end proc:
seq(A004738(n),n=1..30) ; #R. J. Mathar, Feb 14 2019

row[n_] := Range[n, 1, -1] ~Join~ Range[2, n];
Array[row, 10] // Flatten (* Jean-François Alcover, Apr 19 2020 *)

a(n)= floor(sqrt(n)+1/2)+1-abs(n-1-(floor(sqrt(n)+1/2)-1/2)^2)

from math import isqrt
def A004738(n): return abs((t:=isqrt(n-1))*(t+1)-n+1)+1 # Chai Wah Wu, Mar 01 2025

a(n) = floor(sqrt(n) + 1/2) + 1 - abs(n - 1 - (floor(sqrt(n) + 1/2))^2). - Benoit Cloitre, Feb 08 2003
From Boris Putievskiy, Jan 24 2013: (Start)
For the general case, a(n) = m*v + (2*v-1)*(t*t-n) + t, where t = floor(sqrt(n) - 1/2) + 1 and v = floor((n-1)/t) - t + 1.
For m=2, a(n) = 2*v + (2*v-1)*(t*t-n) + t, where t = floor(sqrt(n) - 1/2) + 1 and v = floor((n-1)/t) - t + 1. (End)

More terms from Patrick De Geest, Jun 15 1998

A143182 Triangle T(n,m) = 1 + abs(n-2*m), read by rows, 0<=m<=n.

Original entry on oeis.org

1, 2, 2, 3, 1, 3, 4, 2, 2, 4, 5, 3, 1, 3, 5, 6, 4, 2, 2, 4, 6, 7, 5, 3, 1, 3, 5, 7, 8, 6, 4, 2, 2, 4, 6, 8, 9, 7, 5, 3, 1, 3, 5, 7, 9, 10, 8, 6, 4, 2, 2, 4, 6, 8, 10, 11, 9, 7, 5, 3, 1, 3, 5, 7, 9, 11, 12, 10, 8, 6, 4, 2, 2, 4, 6, 8, 10, 12, 13, 11, 9, 7, 5, 3, 1, 3, 5, 7, 9, 11, 13

Offset: 0

Roger L. Bagula and Gary W. Adamson, Oct 17 2008

From Boris Putievskiy, Jan 15 2013: (Start)

General case see A187760. Let m be natural number. Table T(n,k) n, k > 0, T(n,k)=n-k+1, if n>=k, T(n,k)=k-n+m-1, if n < k. Table T(n,k) read by antidiagonals. The first column of the table T(n,1) is the sequence of the natural numbers A000027. In all columns with number k (k > 1) the segment with the length of (k-1): {m+k-2, m+k-3, ..., m} shifts the sequence A000027. For m=1 the result is A220073, for m=2 the result is A143182. (End)

			From _Boris Putievskiy_, Jan 15 2013: (Start)
The start of the sequence as table:
1...2...3...4...5...6...7...8...9..10..11...
2...1...2...3...4...5...6...7...8...9..10...
3...2...1...2...3...4...5...6...7...8...9...
4...3...2...1...2...3...4...5...6...7...8...
5...4...3...2...1...2...3...4...5...6...7...
6...5...4...3...2...1...2...3...4...5...6...
7...6...5...4...3...2...1...2...3...4...5...
8...7...6...5...4...3...2...1...2...3...4...
9...8...7...6...5...4...3...2...1...2...3...
10..9...8...7...6...5...4...3...2...1...2...
11.10...9...8...7...6...5...4...3...2...1...
. . .
The start of the sequence as triangle array read by rows: (End)
   1;
   2, 2;
   3, 1, 3;
   4, 2, 2, 4;
   5, 3, 1, 3, 5;
   6, 4, 2, 2, 4, 6;
   7, 5, 3, 1, 3, 5, 7;
   8, 6, 4, 2, 2, 4, 6, 8;
   9, 7, 5, 3, 1, 3, 5, 7, 9;
  10, 8, 6, 4, 2, 2, 4, 6, 8, 10;
  11, 9, 7, 5, 3, 1, 3, 5, 7,  9, 11;
. . .
Row number r contains r numbers: r, r-2,...3,1,3,...r-2,r if r is odd,
r, r-2,...2,2,...r-2,r, if r is even. - _Boris Putievskiy_, Jan 15 2013

G. C. Greubel, Rows n= 0.100 of triangle, flattened
Boris Putievskiy, Transformations [Of] Integer Sequences And Pairing Functions, arXiv:1212.2732 [math.CO], 2012.

Cf. A049581 (subtract 1's), A074148 (row sums), A000027, A220073, A187760.

Flat(List([0..15], n-> List([0..n], k-> 1+AbsInt(n-2*k) ))); # G. C. Greubel, Jul 23 2019

[1+Abs(n-2*k): k in [0..n], n in [0..15]]; // G. C. Greubel, Jul 23 2019

T[n_, m_]:= 1+Abs[(1+n-m) - (1+m)]; Table[Table[t[n, m], {m,0,n}], {n, 0, 15}]//Flatten

for(n=0,15, for(k=0,n, print1(1+abs(n-2*k), ", "))) \\ G. C. Greubel, Jul 23 2019

[[1+abs(n-2*k) for k in (0..n)] for n in (0..15)] # G. C. Greubel, Jul 23 2019

Symmetry: T(n,m) = T(n,n-m).
From Boris Putievskiy, Jan 15 2013: (Start)
For the general case
a(n) = |(t+1)^2 - 2n| + m*floor((t^2+3t+2-2n)/(t+1)),
where t = floor((-1+sqrt(8*n-7))/2).
For m = 2
a(n) = |(t+1)^2 - 2n| + 2*floor((t^2+3t+2-2n)/(t+1)),
where t=floor((-1+sqrt(8*n-7))/2). (End)

Offset and row sums corrected by R. J. Mathar, Jul 05 2012

A220073 Mirror of the triangle A130517.

Original entry on oeis.org

1, 1, 2, 2, 1, 3, 3, 1, 2, 4, 4, 2, 1, 3, 5, 5, 3, 1, 2, 4, 6, 6, 4, 2, 1, 3, 5, 7, 7, 5, 3, 1, 2, 4, 6, 8, 8, 6, 4, 2, 1, 3, 5, 7, 9, 9, 7, 5, 3, 1, 2, 4, 6, 8, 10, 10, 8, 6, 4, 2, 1, 3, 5, 7, 9, 11, 11, 9, 7, 5, 3, 1, 2, 4, 6, 8, 10, 12, 12, 10, 8, 6, 4, 2

Offset: 1

Reinhard Zumkeller, Dec 03 2012

T(n,k) = A130517(n,n-k+1), 1 <= k <= n;
T(n,n) = T(n,1) + 1.
From Boris Putievskiy, Jan 15 2013: (Start)
General case see A187760. Let m be natural number. Table T(n,k) n, k > 0, T(n,k)=n-k+1, if n>=k, T(n,k)=k-n+m-1, if n < k.  Table T(n,k) read by antidiagonals. The first column of the table T(n,1) is the sequence of the natural numbers A000027. In all columns with number k (k > 1) the segment with the length of (k-1): {m+k-2, m+k-3, ..., m}  shifts the sequence A000027. For m=1 the result is A220073, for m=2 the result is A143182. (End)
First inverse function (numbers of rows) for pairing function A209293. - Boris Putievskiy, Jan 28 2013

			From _Boris Putievskiy_, Jan 15 2013: (Start)
The start of the sequence as table:
1..1..2..3..4..5..6..7...
2..1..1..2..3..4..5..6...
3..2..1..1..2..3..4..5...
4..3..2..1..1..2..3..4...
5..4..3..2..1..1..2..3...
6..5..4..3..2..1..1..2...
7..6..5..4..3..2..1..1...
8..7..6..5..4..3..2..1...
. . .
The start of the sequence as triangle array read by rows:
1,
1, 2,
2, 1, 3,
3, 1, 2, 4,
4, 2, 1, 3, 5,
5, 3, 1, 2, 4, 6,
6, 4, 2, 1, 3, 5, 7,
7, 5, 3, 1, 2, 4, 6, 8,
. . .
Row number r contains r numbers: r-1, r-3,...,1,...r-2,r.
(End)

Reinhard Zumkeller, Rows n = 1..120 of triangle, flattened
Boris Putievskiy, Transformations [of] Integer Sequences And Pairing Functions arXiv:1212.2732 [math.CO], 2012.

Cf. A028310 (left edge), A000027 (right edge), A000012 (central terms), A000217 (row sums), A220075 (partial sums in rows), A002260, A000027, A143182, A187760, A209293.

a220073 n k = a220073_tabl !! (n-1) !! (k-1)
a220073_row n = a220073_tabl !! (n-1)
a220073_tabl = map reverse a130517_tabl

max = 13;
row[n_] := Join[Range[n, 1, -1], Range[max - n + 1]];
T = Array[row, max];
Table[T[[n - k + 1, k]], {n, 1, max}, {k, n, 1, -1}] // Flatten (* Jean-François Alcover, Sep 11 2017 *)

T(1,1)=1, for n>1: T(n,k)=T(n-1,n-k+1), 1<=k

From Boris Putievskiy, Jan 15 2013: (Start)

For the general case

a(n) = |(t+1)^2 - 2n| + m*floor((t^2+3t+2-2n)/(t+1)),

where t = floor((-1+sqrt(8*n-7))/2).

For m = 2

a(n) = |(t+1)^2 - 2n| + floor((t^2+3t+2-2n)/(t+1)),

where t=floor((-1+sqrt(8*n-7))/2). (End)

A004739 Concatenation of sequences (1,2,2,...,n-1,n-1,n,n,n-1,n-1,...,2,2,1) for n >= 1.

Original entry on oeis.org

1, 1, 1, 2, 2, 1, 1, 2, 3, 3, 2, 1, 1, 2, 3, 4, 4, 3, 2, 1, 1, 2, 3, 4, 5, 5, 4, 3, 2, 1, 1, 2, 3, 4, 5, 6, 6, 5, 4, 3, 2, 1, 1, 2, 3, 4, 5, 6, 7, 7, 6, 5, 4, 3, 2, 1, 1, 2, 3, 4, 5, 6, 7, 8, 8, 7, 6, 5, 4, 3, 2, 1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 9, 8, 7, 6, 5, 4, 3, 2, 1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 10, 9, 8, 7

Offset: 1

R. Muller

From Artur Jasinski, Mar 07 2010: (Start)
Zeta(2, k/p) + Zeta(2, (p-k)/p) = (Pi/sin((Pi*a(n))/p))*2, where p=2,3,4, k=1..p-1.
This sequence is the odd subset of A003983 for odd p=3,5,7,9,....
For the even subset of A003983 see A004737. (End)
Table T(n,k) n, k > 0, T(n,k) = n-k+1, if n >= k, T(n,k) = k-n, if n < k.  Table read by sides of squares from T(1,n) to T(n,n), then from T(n,n) to T(n,1). General case A209301. Let m be a natural number. The first column of the table T(n,1) is the sequence of the natural numbers A000027. In all columns with number k (k > 1) the segment with the length of (k-1): {m+k-2, m+k-3, ..., m} shifts the sequence A000027. For m=1 the result is A004739, for m=2 the result is A004738, for m=3 the result is A209301. - Boris Putievskiy, Jan 24 2013

			From _Boris Putievskiy_, Jan 24 2013: (Start)
The start of the sequence as table:
  1, 1, 2, 3, 4, 5, 6, ...
  2, 1, 1, 2, 3, 4, 5, ...
  3, 2, 1, 1, 2, 3, 4, ...
  4, 3, 2, 1, 1, 2, 3, ...
  5, 4, 3, 2, 1, 1, 2, ...
  6, 5, 4, 3, 2, 1, 1, ...
  7, 6, 5, 4, 3, 2, 1, ...
  ...
The start of the sequence as triangle array read by rows:
  1;
  1, 1, 2;
  2, 1, 1, 2, 3;
  3, 2, 1, 1, 2, 3, 4;
  4, 3, 2, 1, 1, 2, 3, 4, 5;
  5, 4, 3, 2, 1, 1, 2, 3, 4, 5, 6;
  6, 5, 4, 3, 2, 1, 1, 2, 3, 4, 5, 6, 7;
  ...
Row number r contains 2*r - 1 numbers: r-1, r-2, ..., 1, 1, 2, ..., r. (End)

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
Boris Putievskiy, Transformations [Of] Integer Sequences And Pairing Functions, arXiv preprint arXiv:1212.2732 [math.CO], 2012.
F. Smarandache, Collected Papers, Vol. II
F. Smarandache, Sequences of Numbers Involved in Unsolved Problems.
Eric Weisstein's World of Mathematics, Smarandache Sequences

Cf. A004737, A004738, A004731, A003983, A079813, A187760, A004738, A209301.

a004739 n = a004739_list !! (n-1)
a004739_list = concat $ map (\n -> [1..n] ++ [n,n-1..1]) [1..]
-- Reinhard Zumkeller, Mar 26 2011

aa = {}; Do[Do[AppendTo[aa, (p/Pi) ArcSin[Sqrt[1/((1/Pi^2) (Zeta[2, k/p] + Zeta[2, (p - k)/p]))]]], {k, 1, p - 1}], {p, 3, 50, 2}]; Round[N[aa, 50]] (* Artur Jasinski, Mar 07 2010 *)

From Boris Putievskiy, Jan 24 2013: (Start)
For the general case,
a(n) = m*v + (2*v-1)*(t*t-n) + t, where t = floor(sqrt(n) - 1/2) + 1 and v = floor((n-1)/t) - t + 1.
For m=1,
a(n) = v + (2*v-1)*(t*t-n) + t, where t = floor(sqrt(n) - 1/2) + 1 and v = floor((n-1)/t) - t + 1. (End)

More terms from Patrick De Geest, Jun 15 1998

A209301 Table T(n,k) n, k > 0, T(n,k)=n-k+1, if n>=k, T(n,k)=k-n+2, if n < k. Table read by sides of squares from T(1,n) to T(n,n), then from T(n,n) to T(n,1).

Original entry on oeis.org

1, 3, 1, 2, 4, 3, 1, 2, 3, 5, 4, 3, 1, 2, 3, 4, 6, 5, 4, 3, 1, 2, 3, 4, 5, 7, 6, 5, 4, 3, 1, 2, 3, 4, 5, 6, 8, 7, 6, 5, 4, 3, 1, 2, 3, 4, 5, 6, 7, 9, 8, 7, 6, 5, 4, 3, 1, 2, 3, 4, 5, 6, 7, 8, 10, 9, 8, 7, 6, 5, 4, 3, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 10, 9, 8, 7

Offset: 1

Boris Putievskiy, Jan 18 2013

In general, let m be natural number. The first column of the table T(n,1) is the sequence of the natural numbers A000027. In all columns with number k (k > 1) the segment with the length of (k-1): {m+k-2, m+k-3, ..., m} shifts the sequence A000027. For m=1 the result is A004739, for m=2 the result is A004738. This sequence is result for m=3.

			The start of the sequence as table for the general case:
  1,   m, m+1, m+2, m+3, m+4, m+5, ...
  2,   1,   m, m+1, m+2, m+3, m+4, ...
  3,   2,   1,   m, m+1, m+2, m+3, ...
  4,   3,   2,   1,   m, m+1, m+2, ...
  5,   4,   3,   2,   1,   m, m+1, ...
  6,   5,   4,   3,   2,   1,   m, ...
  7,   6,   5,   4,   3,   2,   1, ...
  ...
The start of the sequence as triangle array read by rows for the general case:
  1;
  m,1,2;
  m+1,m,1,2,3;
  m+2,m+1,m,1,2,3,4;
  m+3,m+2,m+1,m,1,2,3,4,5;
  m+4, m+3,m+2,m+1,m,1,2,3,4,5,6;
  m+5, m+4, m+3,m+2,m+1,m,1,2,3,4,5,6,7;
  ...
Row number r contains 2*r -1 numbers: m+r-2, m+r-1,...m,1,2,...r.
The start of the sequence as triangle array read by rows for m=3:
  1;
  3,1,2;
  4,3,1,2,3;
  5,4,3,1,2,3,4;
  6,5,4,3,1,2,3,4,5;
  7,6,5,4,3,1,2,3,4,5,6;
  8,7,6,5,4,3,1,2,3,4,5,6,7;
  ...

Boris Putievskiy, Rows n = 1..140 of triangle, flattened
Boris Putievskiy, Transformations Integer Sequences And Pairing Functions, arXiv:1212.2732 [math.CO], 2012.

Cf. A187760, A004739, A004738.

t=int((math.sqrt(n))-0.5)+1
v=int((n-1)/t)-t+1
result=k*v+(2*v-1)*(t**2-n)+t

For the general case
a(n) = m*v+(2*v-1)*(t*t-n)+t,
where
t = floor(sqrt(n)-1/2)+1,
v = floor((n-1)/t)-t+1.
For m=3
a(n) = 3*v+(2*v-1)*(t*t-n)+t,
where
t = floor(sqrt(n)-1/2)+1,
v = floor((n-1)/t)-t+1.

A209302 Table T(n,k) = max{n+k-1, n+k-1} n, k > 0, read by sides of squares from T(1,n) to T(n,n), then from T(n,n) to T(n,1).

Original entry on oeis.org

1, 2, 3, 2, 3, 4, 5, 4, 3, 4, 5, 6, 7, 6, 5, 4, 5, 6, 7, 8, 9, 8, 7, 6, 5, 6, 7, 8, 9, 10, 11, 10, 9, 8, 7, 6, 7, 8, 9, 10, 11, 12, 13, 12, 11, 10, 9, 8, 7, 8, 9, 10, 11, 12, 13, 14, 15, 14, 13, 12, 11, 10, 9, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 16, 15, 14

Offset: 1

Boris Putievskiy, Jan 18 2013

			The start of the sequence as a table for the general case:
      1   m+1 2*m+1 3*m+1 4*m+1 5*m+1 6*m+1 ...
    m+1   m+2 2*m+2 3*m+2 4*m+2 5*m+2 6*m+2 ...
  2*m+1 2*m+2 2*m+3 3*m+3 4*m+3 5*m+3 6*m+3 ...
  3*m+1 3*m+2 3*m+3 3*m+4 4*m+4 5*m+4 6*m+4 ...
  4*m+1 4*m+2 4*m+3 4*m+4 4*m+5 5*m+5 6*m+5 ...
  5*m+1 5*m+2 5*m+3 5*m+4 5*m+5 5*m+6 6*m+6 ...
  6*m+1 6*m+2 6*m+3 6*m+4 6*m+5 6*m+6 6*m+7 ...
  ...
The start of the sequence as a triangular array read by rows for general case:
      1;
    m+1,   m+2,   m+1;
  2*m+1, 2*m+2, 2*m+3, 2*m+2, 2*m+1;
  3*m+1, 3*m+2, 3*m+3, 3*m+4, 3*m+3, 3*m+2, 3*m+1;
  4*m+1, 4*m+2, 4*m+3, 4*m+4, 4*m+5, 4*m+4, 4*m+3, 4*m+2, 4*m+1;
  ...
Row r contains 2*r-1 terms: r*m+1, r*m+2, ... r*m+r, r*m+r+1, r*m+r, ..., r*m+2, r*m+1.
The start of the sequence as triangle array read by rows for m=1:
  1;
  2,  3,  2;
  3,  4,  5,  4,  3;
  4,  5,  6,  7,  6,  5,  4;
  5,  6,  7,  8,  9,  8,  7,  6,  5;
  6,  7,  8,  9, 10, 11, 10,  9,  8,  7,  6;
  7,  8,  9, 10, 11, 12, 13, 12, 11, 10,  9,  8,  7;
  ...

Boris Putievskiy, Rows n = 1..140 of triangle, flattened
Boris Putievskiy, Transformations Integer Sequences And Pairing Functions, arXiv:1212.2732 [math.CO], 2012.

Cf. A187760.

result = 2*int(math.sqrt(n-1)) - abs(n-int(math.sqrt(n-1))**2 - int(math.sqrt(n-1)) -1) +1

from math import isqrt
def A209302(n): return (k:=(m:=isqrt(n))+(n-m*(m+1)>=1))+abs(k**2-n) # Chai Wah Wu, Jun 08 2025

In general, let m be a natural number. Table T(n,k) = max{m*n+k-m, n+m*k-m}. For the general case,
a(n) = (m+1)*sqrt(n-1) + 1 - |n - floor(sqrt(n-1))^2 - floor(sqrt(n-1))|.
For m=1,
a(n) = 2*sqrt(n-1) + 1 - |n - floor(sqrt(n-1))^2 - floor(sqrt(n-1))|.
a(n) = t + |t^2 - n|, where t = floor(sqrt(n)+1/2). - Ridouane Oudra, May 07 2019

Showing 1-6 of 6 results.

cp's OEIS Frontend

A004738 Concatenation of sequences (1,2,...,n-1,n,n-1,...,2) for n >= 2.

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A143182 Triangle T(n,m) = 1 + abs(n-2*m), read by rows, 0<=m<=n.

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A220073 Mirror of the triangle A130517.

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A004739 Concatenation of sequences (1,2,2,...,n-1,n-1,n,n,n-1,n-1,...,2,2,1) for n >= 1.

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A209301 Table T(n,k) n, k > 0, T(n,k)=n-k+1, if n>=k, T(n,k)=k-n+2, if n < k. Table read by sides of squares from T(1,n) to T(n,n), then from T(n,n) to T(n,1).

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A209302 Table T(n,k) = max{n+k-1, n+k-1} n, k > 0, read by sides of squares from T(1,n) to T(n,n), then from T(n,n) to T(n,1).

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Python

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