A109228 Numbers k such that k divides A109227(k); or k such that A109227(k) is a Niven number.

1, 3, 9, 17, 159, 5607, 15219, 54651, 56403, 100147, 120957

Offset

1,2

Comments

a(12) > 2*10^5, if it exists.

Links

Table of n, a(n) for n=1..11.

Example

a(2) = 3 because A109227(3) = 1101 and 1101/3 = 367.

Mathematica

Select[Range[160], Divisible[FromDigits[Boole @ PrimeQ[Range[Prime[#]]]], #] &] (* Amiram Eldar, Aug 18 2020 *)

Crossrefs

Cf. A005349, A109227.

Sequence in context: A056405 A009216 A103072 * A355636 A103162 A310331

Adjacent sequences: A109225 A109226 A109227 * A109229 A109230 A109231

Keyword

nonn,base,more

Author

Jason Earls, Jun 23 2005

Extensions

a(6)-a(11) from Amiram Eldar, Aug 18 2020

Status

approved