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A333578
Numbers k such that a division occurs in A330139(k).
1
5, 12, 21, 172, 15277, 703981, 2060911, 6663113
OFFSET
1,1
COMMENTS
Is this sequence infinite?
EXAMPLE
5 is in this sequence because a division occurs in A330139(5).
MATHEMATICA
seq = {}; n1 = n2 = 1; Do[n3 = n1 + n2; If[Divisible[n3, n], n3/=n; AppendTo[seq, n]]; n1 = n2; n2 = n3, {n, 3, 2*10^4}]; seq (* Amiram Eldar, Mar 28 2020 *)
PROG
(C#)
static void Main(string[] args)
{
BigInteger[] n = new BigInteger[3];
BigInteger count = 3;
n[0] = 1;
n[1] = 1;
short a = 0;
while (a == 0)
{
n[2] = n[1] + n[0];
if (n[2] % count == 0)
{
n[2] = n[2] / count;
Console.WriteLine(count);
}
n[0] = n[1];
n[1] = n[2];
count++;
}
}
(PARI) lista(nn) = {my(x = 1, y = 1, z); for (n=3, nn, z = x + y; if ((z % n) == 0, z = z/n; print1(n, ", ")); x = y; y = z; ); } \\ Michel Marcus, Mar 27 2020
CROSSREFS
Cf. A330139.
Sequence in context: A345714 A242338 A217649 * A131976 A074376 A293502
KEYWORD
nonn,more
AUTHOR
Eder Vanzei, Mar 27 2020
STATUS
approved