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A268594
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Numbers n of the form p^k - k = q^i - i for primes p < q.
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3
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2, 12, 58, 238, 3120, 6856, 29788, 50650, 65520, 161046, 262126, 300760, 1295026, 3442948, 9393928, 13997518, 21253930, 49430860, 84604516, 95443990, 237176656, 329939368, 384240580, 487443400, 633839776, 893871732, 904231060, 1284365500, 1605723208, 3183010108, 3301293166, 3588604288, 3936827536
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OFFSET
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1,1
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LINKS
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EXAMPLE
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50650 = 37^3-3 = 50651^1-1.
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PROG
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(PARI) is(n)=my(p); sum(e=1, logint(n, 2)+1, ispower(n+e, e, &p)&&isprime(p))>1 \\ Charles R Greathouse IV, Feb 08 2016
(PARI) list(lim)=my(v=List([2]), q, n); for(e=3, logint(1+lim\=1, 2), forprime(p=2, sqrtnint(lim+e, e), if(sum(i=1, e-1, n=p^e-e; ispower(n+i, i, &q) && isprime(q)), listput(v, n)))); Set(v) \\ Charles R Greathouse IV, Feb 08 2016
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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