18192

Appears in sequences

• E.g.f. exp(x*tan(x)) (even powers only).at n=4A009252
• Decimal part of cube root of a(n) starts with 3: first term of runs.at n=24A034129
• Convolution triangle of A002605(n) (generalized (2,2)-Fibonacci), n>=0.at n=46A073387
• Convolution of A002605(n) (generalized (2,2)-Fibonacci), n >= 0, with itself.at n=8A073388
• Natural numbers written out with their digits grouped in sets of 5 (leading zeros omitted).at n=5A091341
• Number of 1's that appear among all ternary strings of length n that contain no consecutive 1's.at n=9A109634
• Triangle read by rows: T(n,k) is the number of ternary sequences of length n containing k subsequences 00 (n>=0, 0<=k<=max(0,n-1)).at n=47A118357
• Index of first occurrence of n in A154404.at n=39A154952
• Number of binary strings of length n with equal numbers of 00011 and 01101 substrings.at n=15A164232
• G.f. satisfies: A(A(x)) = Sum_{n>=1} a(n)*x^n / (1-2^n*x)^n, where g.f. A(x) = Sum_{n>=1} a(n)*x^n.at n=4A193204
• Put the natural numbers together without spaces and read them five at a time advancing one space each time.at n=25A193493
• Triangle of coefficients of polynomials v(n,x) jointly generated with A208757; see the Formula section.at n=64A208758
• Triangle of coefficients of polynomials u(n,x) jointly generated with A208760; see the Formula section.at n=53A208759
• Number of 2 X 2 matrices having all elements in {-n,...n} and determinant 3.at n=37A209986
• Expansion of psi(x^3) * phi(-x)^2 / phi(-x^2) in power of x where phi(), psi() are Ramanujan theta functions.at n=8A210656
• Number of tilings of a 5 X n rectangle using n pentominoes of shapes F, U, N.at n=27A234931
• Number of compositions of n having exactly three fixed points.at n=14A240738
• Number of (3+1)X(n+1) 0..1 arrays with every 2X2 subblock ne-sw antidiagonal difference unequal to its neighbors horizontally and nw+se diagonal sum unequal to its neighbors vertically.at n=11A253700
• G.f.: Product_{k >= 0} ((1 + x^(2*k+1)) / (1 - x^(2*k+1)))^k.at n=32A361008
• Expansion of Sum_{k>0} (1/(1+x^k)^4 - 1).at n=43A363631