experimental-projects/oeis-research/Michel Marcus/Number of Lucas divisors of the n-th Lucas number/prog.sf

#!/usr/bin/ruby

# Number of Lucas divisors of the n-th Lucas number
# https://oeis.org/A356122

func a(k) {

    return 2 if (k == 0)
    return 1 if (k == 1)

    var n = k.lucas
    var count = 0
    for k in (0..Inf) {
        var t = k.lucas
        if (t.divides(n)) {
            ++count
        }
        break if (t >= n)
    }
    return count
}

for n in (0..10) {
    say "#{n} #{a(n)}"
}

__END__

# PARI/GP program:

a(n) = if(n==1, return(1)); my(k=fibonacci(n+1)+fibonacci(n-1),c=0,x=2,y=1); while(x <= k, if(k%x == 0, c++); [x,y]=[y,x+y]); c;