Problem statement
Some prime numbers can be written as the sum of two consecutive lower primes plus / minus one :
Like this for example, 7 = 3 + 5 - 1, and 11 = 5 + 7 - 1.
In a vector, list such prime numbers lower than a given -input- positive integer m.
Examples
  • m = 50 => p = [7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43];
  • m = 100 => p = [7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 53, 59, 61, 67, 79, 83, 89];
  • m = 200 => p = [7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 53, 59, 61, 67, 79, 83, 89, 101, 113, 127, 131, 151, 163, 173, 197, 199];
Fobidden functions
  • regexp
  • str2num
  • assignin
  • echo
See also
Solve

Solution Stats

116 Solutions

55 Solvers

Last Solution submitted on Feb 06, 2026

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泽伟 Peter Dennis Harsh Mali

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