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PROG
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(PARI) is(n)=numdiv(n)==26 && numdiv(n+1)==26
(PARI) has(n)=if(n%4==2, ispower(n/2, 12, &n) && isprime(n), bitand(n, 8191)==4096 && isprime(n>>12) && n>8192) \\ check if n is even with 26 divisors
list(lim)=my(v=List(), t); forprime(p=2, sqrtnint(lim\=1, 25), t=p^25; if(has(t+1), listput(v, t)); if(has(t-1), listput(v, t-1))); forprime(p=3, sqrtnint(lim\3, 12), my(p12=p^12); forprime(q=3, lim\p12, if(p==q, next); t=p12*q; if(has(t+1), listput(v, t)); if(has(t-1), listput(v, t-1)))); Set(v)
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