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Greatest prime factor of the concatenation of terms of the n-th row of the triangle formed by the Stirling number of the second kind.
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%I #4 Dec 05 2013 19:56:58

%S 11,131,587,1646443,6827,18011869,9120065483,363724245921599,

%T 975761724248252813688864599,17542508725666616033,

%U 111131968773953028264114836512440131291369683

%N Greatest prime factor of the concatenation of terms of the n-th row of the triangle formed by the Stirling number of the second kind.

%C Are these concatenations squarefree?

%F a(n) = A006530[A061113(n)]. - _R. J. Mathar_, Aug 07 2007

%e a(4) = 587 is the greatest prime factor of 1761 =3*587.

%Y Cf. A100755, A100756, A100757, A008277.

%K base,easy,nonn

%O 2,1

%A _Amarnath Murthy_, Nov 23 2004

%E More terms from _R. J. Mathar_, Aug 07 2007