1825201

Appears in sequences

• Numbers k such that k and floor[k/3] are both squares; i.e., squares which remain squares when written in base 3 and last digit is removed.at n=7A055793
• Numbers n such that n-1 and n are a pair of consecutive powerful numbers.at n=8A078326
• G.f.: -(1-3*x^2-x^3)/(1+4*x-4*x^3-x^4).at n=11A097948
• Duplicate of A078326.at n=8A118893
• a(n) = (1-2*n^2)^2.at n=26A239607
• a(n) = sin( arcsin(n)- 2*arccos(n) )^2.at n=7A239608