A109228 - OEIS

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

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OFFSET

1,2

COMMENTS

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

LINKS

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

KEYWORD

nonn,base,more

AUTHOR

Jason Earls, Jun 23 2005

EXTENSIONS

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

STATUS

approved