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%I #17 Oct 26 2014 17:29:41
%S 6,837,85094,8537238,853922530,85397212652,8539729843352,
%T 853973398759468,85397341863406230,8539734219628209684,
%U 853973422224398765940,85397342226185298383510,8539734222671268708689351,853973422267317150596927230,85397342226735418150399772016
%N Product of the first n digits of Pi (treated as a number) and the first n digits of e (treated as a number).
%F a(n+1) = floor(10^n * Pi) * floor(10^n * e). - _Charles R Greathouse IV_, Oct 21 2014
%F a(n) ~ Pi*e/100 * 100^n + O(10^n). - _Charles R Greathouse IV_, Oct 21 2014
%F a(n) = A011543(n-1)*A011545(n-1). - _Michel Marcus_, Oct 26 2014
%e The first digit of Pi is 3, the first digit of e is 2, and 2 times 3 = 6, so a(1) = 6. The first two digits of Pi are 31, the first two digits of e are 27, and 31 times 27 = 837, so a(2) = 837.
%t Module[{nn=20,p,e},p=RealDigits[Pi,10,nn][[1]];e=RealDigits[E,10,nn][[1]];Table[FromDigits[Take[p,n]]FromDigits[Take[e,n]],{n,nn}]]
%o (PARI) a(n)=n--; floor(10^n * Pi) * floor(10^n * exp(1)) \\ _Charles R Greathouse IV_, Oct 21 2014
%Y Cf. A011543 (e), A011545 (Pi).
%K nonn,base
%O 1,1
%A _Harvey P. Dale_, Oct 21 2014