4356618

Appears in sequences

• Number of binary vectors of length n containing no singletons.at n=33A006355
• a(n) = 2*Fibonacci(2*n+2).at n=15A025169
• Number of distinct permutations generated by shuffling n cards with "clump size" <= 2.at n=29A047992
• Layer counting sequence for hyperbolic tessellation by cuspidal triangles of angles (Pi/3,Pi/3,0) (this is the classical modular tessellation).at n=30A054886
• a(0) = 1, then twice the Fibonacci sequence.at n=32A055389
• a(n) = 2*Fibonacci(n) - (1 - (-1)^n)/2.at n=32A062114
• Number of ways to tile a 3 X 2n room with 1 X 2 Tatami mats. At most 3 Tatami mats may meet at a point.at n=30A068922
• Numbers with two representations as the sum of two Fibonacci numbers.at n=29A078642
• Number of meaningful differential operations of the n-th order on the space R^6.at n=28A090991
• A Chebyshev transform of (1+3x)/(1-3x).at n=15A099858
• Number of permutations avoiding the patterns {1432,2431,3412,3421,4132,4231,4312,4321}; number of strong sorting class based on 1432.at n=16A111282
• a(n) = 2*F(n-1) = L(n) - F(n), where F(n) and L(n) are Fibonacci and Lucas numbers respectively.at n=33A118658
• Expansion of g.f. x*(1+x+x^2)/(1-x-x^2).at n=31A128588
• Expansion of x*(1+2*x)/( (x^2-x-1)*(x^2+x-1) ).at n=31A133586
• Inverse score permutation of an Fibonacci -anti-Fibonacci zero sum game of 2 X 2 matrices.at n=20A134016
• First differences of A135992.at n=31A135994
• Sum of Fibonacci numbers between F(-n)....F(n), inclusive.at n=31A140833
• Sum of Fibonacci numbers between F(-n)....F(n), inclusive.at n=32A140833
• Number of n X 2 binary arrays with all 1s connected, a path of 1s from top row to bottom row, and no 1 having more than two 1s adjacent.at n=29A163714
• Number of n X 2 binary arrays with all 1's connected, all corners 1, and no 1 having more than two 1's adjacent.at n=33A163733