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Numbers n for which A034448(n)-n is equal to n-A048250(n).
4

%I #7 Jun 07 2019 01:56:01

%S 1,4,24,240,349440

%N Numbers n for which A034448(n)-n is equal to n-A048250(n).

%C No other terms below 536870912 (2^29).

%C a(6) > 10^12, if it exists. - _Giovanni Resta_, Jun 07 2019

%o (PARI)

%o A034448(n) = { my(f=factorint(n)); prod(k=1, #f~, 1+(f[k, 1]^f[k, 2])); };

%o A048250(n) = factorback(apply(p -> p+1,factor(n)[,1]));

%o isA325963(n) = ((A034448(n)-n) == (n-A048250(n)));

%Y Cf. A034448, A048250, A034460, A325313.

%Y Positions of zeros in A325977.

%K nonn,more

%O 1,2

%A _Antti Karttunen_, Jun 04 2019