A288985 - OEIS

%I #14 Jun 23 2017 19:14:07

%S 117649,177147,531441,823543,1048576,1594323,1771561,1953125,2097152,

%T 4194304,4782969,4826809,5764801,8388608,9765625

%N Numbers n for which A287874(n) < n, where A287874 is the concatenation of the prime factorization, all written in binary.

%C A287874 is the concatenation of the prime factorization (without exponents equal to 1), all written in binary (so the result has only digits 0 and 1). Here the result of this operation is considered as a decimal number. For example, the first term is 117649 because this numer is larger than the value A287874(117649) = 111110 (even when this is considered as a decimal and not binary number).

%o (PARI) forcomposite(n=1,1e7,A287874(n)<n&&print1(n","))

%Y Cf. A287874.

%K nonn,base

%O 1,1

%A _M. F. Hasler_, Jun 21 2017