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A087280 Solutions n of max(m+d(m))=n+2 for m<n; d(m) is the number of divisors of m. 0

%I #10 Dec 01 2018 10:36:28

%S 5,8,10,12,24

%N Solutions n of max(m+d(m))=n+2 for m<n; d(m) is the number of divisors of m.

%C It is not known if there are other terms. There are no more terms < 10^10.

%D R. K. Guy, Unsolved Problems in Number Theory, section B8.

%H Paul Erdos, <a href="https://www.jstor.org/stable/2689842">Some Unconventional Problems in Number Theory</a>, Mathematics Magazine, Vol. 52, No. 2, Mar., 1979, pp. 67-70. See Problem 4. p. 68.

%e The largest value of m+d(m) for m < n=8 is 6+d(6)=10 = n+2, so 8 is in the sequence.

%K nonn,more

%O 1,1

%A _Jud McCranie_, Aug 28 2003

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