A329368 - OEIS

A329368

Partition the decimal expansion of Pi into non-overlapping strings of length 10: 3141592653, 5897932384,..; a(n) is the position of the strings where digits are different from each other.

%I #19 Apr 29 2020 09:43:02

%S 7,548,3113,11665,11728,14305,15762,19177,23288,28259,35603,37613,

%T 40595,40740,41477,52108,54085,54367,62272,74856,75082,75178,82919,

%U 83591,92284,94936,103849,105419,105832,108875,111962,115152,117919,118976,121112,124121,128505

%N Partition the decimal expansion of Pi into non-overlapping strings of length 10: 3141592653, 5897932384,..; a(n) is the position of the strings where digits are different from each other.

%D David Blatner, The Joy of Pi, Walker and Co., NY, 1997; page 91.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PiDigits.html">Pi Digits</a>

%e a(1) = 7, because such a string first occur at the 7th string: 4592307816 (i.e., 61-70 digits of Pi).

%t q[i_]:=q[i]=Take[RealDigits[Pi,10,10i][[1]],-10];

%t a={}; Do[If[Length@Union@q[i]==10, AppendTo[a,i]], {i,130000}]

%t a

%Y Cf. A000796, A014976, A050278, A096760, A101815, A101816, A107115.

%K nonn,base

%O 1,1

%A _XU Pingya_, Apr 27 2020