|
%I #11 Mar 20 2015 05:25:17
%S 3,3,18,189,247,993,993,3164,22045,23345
%N Smallest number k such that in its decimal representation the first n digits of Pi=3.14... are contained in 11^k.
%C a(11) > 40000. - _Robert G. Wilson v_, Aug 19 2004
%e n=3, '314': 11^18 = 5559917313492231481, therefore a(3)=18: floor(11^a(3) / 100) mod 1000 = 314.
%t f[0] = 1; f[n_] := f[n] = Block[{pi = StringTake[ ToString[ RealDigits[Pi, 10, n][[1]]], {2, -2}], k = f[n - 1]}, While[ StringPosition[ ToString[ IntegerDigits[11^k]], pi] == {}, k++ ]; k]; (* _Robert G. Wilson v_, Aug 19 2004 *)
%Y Cf. A001020, A000796.
%K nonn,base
%O 1,1
%A _Reinhard Zumkeller_, Aug 18 2004
%E a(9)-a(10) from _Robert G. Wilson v_, Aug 19 2004
|
