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%I #11 Jan 15 2022 22:26:05
%S 36,2296,344224,66795904,2123921902809088,55917383475391234048,
%T 113139095670780538912768,18936964716073275231635792697644548096,
%U 17844842231875188005737387074890396164121166838056340379818586412691750912
%N Product of n-th perfect number and n-th perfect number written backwards.
%H Omar E. Pol, <a href="http://www.polprimos.com">Determinacion geometrica de los numeros primos y perfectos</a>.
%F a(n) = A000396(n)*A135624(n).
%e a(2)=2296 because the second perfect number is 28 and 28*82=2296.
%t # IntegerReverse[#]&/@PerfectNumber[Range[10]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Nov 29 2020 *)
%Y Cf. A000396, A133019, A135624.
%K base,nonn
%O 1,1
%A _Omar E. Pol_, Feb 20 2008
%E More terms from _R. J. Mathar_, Jun 24 2009