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ZCubes/Mersenne Primes and Perfect Numbers (view source)
Revision as of 08:34, 24 March 2020
, 08:34, 24 March 2020→Video
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==Code==
a=2n^(1..700);
units.on;
a.$(x=>[x,x-1n,(ISPRIME(x<>n-1n))])
.filter(r=>r[0][2])
1..10000
.filter(n=>SUM(PROPERDIVISORS(n))==n)
[3,7,31,127,8191,131071].$(""x*(x+1)/2"")"