What are the known titanic primes (primes with at least 1000 decimal digits) that are not Mersenne primes?

arithmetic/titanic.primes New

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Problem

What are the known titanic primes (primes with at least 1000 decimal
digits) that are not Mersenne primes?

[ Editor: problem statement reconstructed from F. Morain's request to
complete his table. ]

Show solution

I am trying to update my table of the so-called titanic primes, that
is prime numbers with at least 1000 decimal digits.  Using the article
'Ten extraordinary primes' (R. Ondrejka, J. Recreational Math., vol.
18(2), 1985-1986, p.87-92) I got the first ones and then I added some
others.  Did I miss some?  As a matter of fact, I am only interested
in non Mersenne primes.

    Type                        digits   when   who

I : k.10^n+1
   k     n
  6006  7090                     7094    1985    H. Dubner
217833  7150                     7156    1985    H. Dubner

II : k.10^n-1
   k     n
   2    3020                     3021    1985    H. C. Williams

III : twin primes
     520995090. 2^6624+-1        2003    1984    A. O. L. Atkin, N. W. Rickert
43690485351513.10^1995+-1        2009    1985    H. Dubner
     107570463.10^2250+-1        2259    1985    H. Dubner

IV : k!+1
   k
1477                             4042    1984    H. Dubner

V  : product(primes <= k)-1
   k
6569                             2811    1984    H. Dubner

VI : palindromic 10^(2n)+k.10^n+1
   k     n
   3    1488                     2977    1984    H. Dubner

VII : none of the types just described

1(1029)1                         1031    1985    H. Dubner & H. C. Williams
 (that is 1 followed by 1029 1-digit, ...)
10(1105)880880(1105)1            2217    1984    H. Dubner
10(1288)23456789987654320(1288)1 2595    1984    ?
2(1439)0(1439)1                  2879    1984    ?
6(1611)0(1611)1                  3223    1984    ?
1(111)2(111)...9(111)0(2284)1    3284    1985    H. Dubner
8423.2^59877+1                  18029    1988(?) Buell, Young

-- F. Morain

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