A099093 -id:A099093 - cp's OEIS frontend

A106344 Triangle read by rows: T(n,k) = binomial(k,n-k) mod 2.

1, 0, 1, 0, 1, 1, 0, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1

Offset: 0

Paul Barry, Apr 29 2005

A skew version of Sierpinski’s triangle A047999. - Johannes W. Meijer, Jun 05 2011
Row sums are A002487(n+1). Diagonal sums are A106345. Inverse is A106346.
Triangle formed by reading T triangle mod 2 with T := A026729, A062110, A084938, A099093, A106344, A109466, A110517, A112883, A130167. - Philippe Deléham, Dec 18 2008

			Triangle begins
  1;
  0, 1;
  0, 1, 1;
  0, 0, 0, 1;
  0, 0, 1, 1, 1;
  0, 0, 0, 1, 0, 1;

G. C. Greubel, Rows n = 0..50, flattened
Thomas Baruchel, Flattening Karatsuba's Recursion Tree into a Single Summation, SN Computer Science (2020) Vol. 1, Article No. 48.
George Beck and Karl Dilcher, A Matrix Related to Stern Polynomials and the Prouhet-Thue-Morse Sequence, arXiv:2106.10400 [math.CO], 2021. See (1.6) p. 2.

Cf. A047999, A002487.
Cf. A106345 (diagonal sums), A106346 (inverse).
Cf. A026729, A062110, A084938, A099093, A106344, A109466, A110517, A112883, A130167.

Flat(List([0..15], n-> List([0..n], k-> (Binomial(k,n-k) mod 2) ))); # G. C. Greubel, Feb 07 2020

[ Binomial(k,n-k) mod 2: k in [0..n], n in [0..15]]; // G. C. Greubel, Feb 07 2020

seq(seq(`mod`(binomial(k, n-k), 2), k = 0..n), n = 0..15); # G. C. Greubel, Feb 07 2020

Table[Mod[Binomial[k, n-k], 2], {n,0,15}, {k,0,n}]//Flatten (* G. C. Greubel, Apr 18 2017 *)

T(n,k) = binomial(k,n-k)%2;
for(n=0,15, for(k=0,n, print1(T(n,k), ", "))) \\ G. C. Greubel, Feb 07 2020

[[ mod(binomial(k,n-k), 2) for k in (0..n)] for n in (0..15)] # G. C. Greubel, Feb 07 2020

A099094 a(n) = 3a(n-2) + 3a(n-3), a(0)=1, a(1)=0, a(2)=3.

Original entry on oeis.org

1, 0, 3, 3, 9, 18, 36, 81, 162, 351, 729, 1539, 3240, 6804, 14337, 30132, 63423, 133407, 280665, 590490, 1242216, 2613465, 5498118, 11567043, 24334749, 51195483, 107705376, 226590696, 476702577, 1002888216, 2109879819, 4438772379

Offset: 0

Paul Barry, Sep 25 2004

Diagonal sums of A099093.
Counts walks (closed) on the graph G(1-vertex; 2-loop, 2-loop, 2-loop, 3-loop, 3-loop, 3-loop). - David Neil McGrath, Jan 16 2015
Number of compositions of n into parts 2 and 3, each of three sorts. - Joerg Arndt, Feb 14 2015

Index entries for linear recurrences with constant coefficients, signature (0,3,3).

CoefficientList[Series[1 / (1 - 3 x^2 - 3 x^3), {x, 0, 40}], x] (* Vincenzo Librandi, Feb 16 2015 *)
LinearRecurrence[{0,3,3},{1,0,3},40] (* Harvey P. Dale, Aug 15 2017 *)

Vec(1/(1-3*x^2-3*x^3) + O(x^50)) \\ Michel Marcus, Jan 17 2015

G.f.: 1/(1 - 3*x^2 - 3*x^3).
a(n) = Sum_{k=0..floor(n/2)} binomial(k, n-2k)*3^k.
Construct the power matrix T(n,j) = [A(n)^*j]*[S(n)^*(j-1)] where A(n) = (0,3,3,0,0,...) and S(n) = (0,1,0,0,...). (* is convolution operation.) Define S^*0 = I. Then T(n,j) counts n-walks containing (j) loops, on the single vertex graph above, and a(n) = Sum_{j=1..n} T(n,j). - David Neil McGrath, Jan 16 2015

Corrected by Philippe Deléham, Dec 18 2008

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A106344 Triangle read by rows: T(n,k) = binomial(k,n-k) mod 2.

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A099094 a(n) = 3a(n-2) + 3a(n-3), a(0)=1, a(1)=0, a(2)=3.

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cp's OEIS Frontend

A106344 Triangle read by rows: T(n,k) = binomial(k,n-k) mod 2.

Views

Author

Keywords

Comments

Examples

Links

Crossrefs

Programs

GAP

Magma

Maple

Mathematica

PARI

Sage

A099094 a(n) = 3*a(n-2) + 3*a(n-3), a(0)=1, a(1)=0, a(2)=3.

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A099094 a(n) = 3a(n-2) + 3a(n-3), a(0)=1, a(1)=0, a(2)=3.