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Composite numbers k such that k is divisible by A318996(k).
0

%I #10 May 03 2021 18:39:50

%S 4,45,304,464,1870,6048,14421,119072,130304,561824,1736150,8124416,

%T 9519296,16303104,26409026

%N Composite numbers k such that k is divisible by A318996(k).

%e a(4) = 464 is a member because it is composite and is divisible by A318996(k) = 16.

%p filter:= proc(n) local D,s,d,v;

%p if isprime(n) then return false fi;

%p D:= numtheory:-divisors(n);

%p s:= convert(D,`+`);

%p v:= add(s mod d, d = D);

%p v > 0 and n mod v = 0

%p end proc:

%p select(filter, [$4..3*10^7]);

%Y Cf. A318996.

%K nonn,more

%O 1,1

%A _J. M. Bergot_ and _Robert Israel_, May 03 2021