Problems & Puzzles:
Collection 20th
Coll.20th-019.
m +/-2^k+/-1 integers.
On May 26, 2018 Arkadiusz Wesolowski wrote:
I observed in 2017 that:
1) 247371098958 is a nonnegative even number m such that for all k >= 1
the numbers m + 2^k + 1 and m + 2^k - 1 are composite.
http://oeis.org/A288477
2) 444813635232 is a nonnegative even number m such that for all k >= 1
the absolute values of the numbers m - 2^k + 1 and m - 2^k - 1 are
composite.
http://oeis.org/A289111
Q1. Can you find "smaller" solutions?
Q2. Are there any nonnegative even numbers that cannot be written in the
form ± 2^k ± 1 ± p where p is a prime number, k∈N and any choice of
signs may be made?
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