13051463049
domain: N
Appears in sequences
- a(n) = floor( a(n-1)/(sqrt(2) - 1) ), with a(0) = 1.at n=27A024537
- a(n) and floor(a(n)/2) are both squares; i.e., squares which remain squares when written in base 2 and last digit is removed.at n=8A055792
- a(n) and floor(a(n)/8) are both squares; i.e., squares that remain squares when written in base 8 and last digit is removed.at n=15A055872
- Numbers k such that k*(k - 1)/2 is a square.at n=14A055997
- Safe perfect powers: perfect powers n such that (n-1)/2 is also a perfect power.at n=7A075127
- Numbers n such that n-1 and n are a pair of consecutive powerful numbers.at n=14A078326
- Repeatedly multiply (1,0,0) by ([1,2,2],[2,1,2],[2,2,3]); sequence gives leading entry.at n=14A090390
- Expansion of g.f. (1-x-x^2)/(1-x-3*x^2-x^3).at n=28A097075
- a(n) = 2*a(n-1) + 2*a(n-3) + a(n-4), a(0) = 1, a(1) = 4, a(2) = 9, a(3) = 20.at n=26A111587
- Consider all Pythagorean triples (X,X+1,Z) ordered by increasing Z; sequence gives Z-X values.at n=13A115599
- Duplicate of A078326.at n=14A118893
- Binomial transform of 1,0,1,0,2,0,4,0,8,0,16,...at n=28A171842