Primes of the form !(k + 1)/2 = Sum_{i=0..k} i!/2.

A124374

Primes of the form !(k + 1)/2 = Sum_{i=0..k} i!/2.

Terms

    a(0) =2a(1) =5a(2) =17a(3) =2957a(4) =23117a(5) =204557a(6) =2018957

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