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%I #12 Jul 24 2024 04:52:29
%S 326,742,314,168,843,168,521,212,212,631,181,181,632,521,155
%N Concatenation of initial digit of n-th Mersenne prime A000668(n), initial digit of n-th even superperfect number A061652(n) and initial digit of n-th perfect number A000396(n).
%C Also, concatenation of initial digit of n-th Mersenne prime A000668(n), initial digit of n-th superperfect number A019279(n) and initial digit of n-th perfect number A000396(n), if there are no odd superperfect numbers.
%C Also, concatenation of A135613(n), A138124(n) and A135617(n).
%H L. C. Noll, <a href="http://www.isthe.com/chongo/tech/math/prime/mersenne.html">Mersenne Prime Digits and Names</a>.
%H Omar E. Pol, <a href="http://www.polprimos.com">Determinacion geometrica de los numeros primos y perfectos</a>.
%Y Cf. A000396, A000668, A019279, A061652, A135613, A135617, A138124, A138817.
%K base,nonn,more
%O 1,1
%A _Omar E. Pol_, Apr 01 2008
%E a(13)-a(15) from _Robert Price_, Jun 16 2019