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Cyclops numbers

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A number is a cyclops number in a given base
b
(base 10 by default) if that number has only one instance of the digit 0, instance which appears precisely in the middle (the eye of the cyclops) of the number. (This obviously implies an odd number of digits.)

Base 2 cyclops numbers

A138148 Cyclops numbers with binary digits only. (Base 2 cyclops numbers.)

{0, 101, 11011, 1110111, 111101111, 11111011111, 1111110111111, 111111101111111, 11111111011111111, 1111111110111111111, 111111111101111111111, 11111111111011111111111, ...}

A129868 Binary palindromic numbers with only one 0 bit. ([Base 2] cyclops numbers A138148, converted to base 10.)

{0, 5, 27, 119, 495, 2015, 8127, 32639, 130815, 523775, 2096127, 8386559, 33550335, 134209535, 536854527, 2147450879, 8589869055, 34359607295, 137438691327, 549755289599, ...}
A138831
n
-th perfect number minus 1, written in base 2. (Subset of A138148, cyclops numbers with binary digits, only.)
{101, 11011, 111101111, 1111110111111, 1111111111110111111111111, 111111111111111101111111111111111, 1111111111111111110111111111111111111, ...}

Base 10 cyclops numbers

A134808 Base 10 cyclops numbers.

{0, 101, 102, 103, 104, 105, 106, 107, 108, 109, 201, 202, 203, 204, 205, 206, 207, 208, 209, 301, 302, 303, 304, 305, 306, 307, 308, 309, 401, 402, 403, 404, 405, 406, 407, 408, ...}

Sequences







  • A?????? Cyclops numbers with circular digits {0, 6, 8, 9}.
  • A160561 Cyclops primes with circular digits {0, 6, 8, 9}.
  • A?????? Cyclops composites with circular digits {0, 6, 8, 9}.