30302

Appears in sequences

• a(n) = Sum_{k=0..n-2} T(n,k) * T(n,k+2), with T given by A026386.at n=6A026953
• Expansion of g.f.: ((1 - x - sqrt(1-6*x+5*x^2))/(2*x))^2.at n=8A045868
• Path-counting array T; each step of a path is (1 right) or (1 up) to a point below line y=x, else (1 right and 1 up) or (1 up) to a point on the line y=x, else (1 left) or (1 up) to a point above line y=x. T(i,j)=number of paths to point (i-j,j), for 1<=j<=i, i >= 1.at n=53A055450
• Triangle of numbers arising in recursive computation of A002212.at n=44A073149
• Sequence A014486 shown in base 4.at n=39A085185
• Sum array of Catalan numbers (A000108) read by upward antidiagonals.at n=47A106534
• Number of nonsquare simple imperfect squared rectangles of order n up to symmetry.at n=18A220165
• Triangle A106534 with reversed rows.at n=52A280470
• Numbers k such that k and k^6 have no digits in common.at n=19A281148
• Even composite integers m such that A004254(m)^2 == 1 (mod m).at n=37A338314