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A109228
Numbers k such that k divides A109227(k); or k such that A109227(k) is a Niven number.
1
1, 3, 9, 17, 159, 5607, 15219, 54651, 56403, 100147, 120957
OFFSET
1,2
COMMENTS
a(12) > 2*10^5, if it exists.
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
Sequence in context: A056405 A009216 A103072 * A376636 A355636 A103162
KEYWORD
nonn,base,more
AUTHOR
Jason Earls, Jun 23 2005
EXTENSIONS
a(6)-a(11) from Amiram Eldar, Aug 18 2020
STATUS
approved