150050

Appears in sequences

• Number of binary vectors of length n containing no singletons.at n=26A006355
• Number of distinct permutations generated by shuffling n cards with "clump size" <= 2.at n=22A047992
• Expansion of 2*x*(1 - x)/(1 - 3*x + x^2).at n=13A052995
• Layer counting sequence for hyperbolic tessellation by cuspidal triangles of angles (Pi/3,Pi/3,0) (this is the classical modular tessellation).at n=23A054886
• a(0) = 1, then twice the Fibonacci sequence.at n=25A055389
• Row sums of array T in A055818; twice the odd-indexed Fibonacci numbers after initial term.at n=13A055819
• a(n) = round(sqrt(a(n-2)^2 + a(n-1)^2)) with a(0) = 1 and a(1) = 2.at n=48A063827
• 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=23A068922
• Numbers with two representations as the sum of two Fibonacci numbers.at n=22A078642
• Number of meaningful differential operations of the n-th order on the space R^6.at n=21A090991
• Expansion of (1+x)^2/(1-x^2-x^4).at n=49A096748
• "Rounded hypotenuses": a(n) = round(sqrt(a(n-1)^2 + a(n-2)^2)), a(1)=1, a(2)=3.at n=47A104804
• a(n) = gcd(Lucas(n)-1, Fibonacci(n)+1).at n=48A115312
• a(n) = 2*F(n-1) = L(n) - F(n), where F(n) and L(n) are Fibonacci and Lucas numbers respectively.at n=26A118658
• Number of base 4 n-digit numbers with adjacent digits differing by one or less.at n=12A126358
• Expansion of g.f. x*(1+x+x^2)/(1-x-x^2).at n=24A128588
• Row sums of triangle A131779.at n=23A131780
• Expansion of x - x^2*(2*x+1)*(x^2-2) / ( (x^2-x-1)*(x^2+x-1) ).at n=24A133585
• First differences of A137976 after having added two leading ones.at n=10A138298
• 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=22A163714