7049156
domain: N
Appears in sequences
- Number of binary vectors of length n containing no singletons.at n=34A006355
- Number of distinct permutations generated by shuffling n cards with "clump size" <= 2.at n=30A047992
- Expansion of 2*x*(1 - x)/(1 - 3*x + x^2).at n=17A052995
- Layer counting sequence for hyperbolic tessellation by cuspidal triangles of angles (Pi/3,Pi/3,0) (this is the classical modular tessellation).at n=31A054886
- a(0) = 1, then twice the Fibonacci sequence.at n=33A055389
- Row sums of array T in A055818; twice the odd-indexed Fibonacci numbers after initial term.at n=17A055819
- 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=31A068922
- Numbers with two representations as the sum of two Fibonacci numbers.at n=30A078642
- Number of meaningful differential operations of the n-th order on the space R^6.at n=29A090991
- a(n) = 2*F(n-1) = L(n) - F(n), where F(n) and L(n) are Fibonacci and Lucas numbers respectively.at n=34A118658
- Number of base 4 n-digit numbers with adjacent digits differing by one or less.at n=16A126358
- Expansion of g.f. x*(1+x+x^2)/(1-x-x^2).at n=32A128588
- Row sums of triangle A131779.at n=31A131780
- Expansion of x - x^2*(2*x+1)*(x^2-2) / ( (x^2-x-1)*(x^2+x-1) ).at n=32A133585
- 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=30A163714
- 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=34A163733
- a(n) = 2*(A000045(n)-(n mod 2)) + 1 + (n mod 2).at n=33A166012
- Values of gcd(Fibonacci(n), Fibonacci(n+3)+2) sorted with no repeats.at n=33A178767
- Denominators of A178381(4*n+3)/A178381(4*n+2).at n=16A179133
- a(n) = (F(2*n-1) + F(2*n+2)) * (5/6 - cos(2*Pi*n/3)/3), where F(n) = Fibonacci(n).at n=16A179134