A288985 Numbers n for which A287874(n) < n, where A287874 is the concatenation of the prime factorization, all written in binary.

117649, 177147, 531441, 823543, 1048576, 1594323, 1771561, 1953125, 2097152, 4194304, 4782969, 4826809, 5764801, 8388608, 9765625

Offset

1,1

Comments

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).

Links

Table of n, a(n) for n=1..15.

Prog

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

Crossrefs

Cf. A287874.

Sequence in context: A251953 A204075 A235068 * A016926 A016986 A017154

Adjacent sequences: A288982 A288983 A288984 * A288986 A288987 A288988

Keyword

nonn,base

Author

M. F. Hasler, Jun 21 2017

Status

approved