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Index of the n-th 9 in the first occurrence of a string of exactly n 9's in the decimal expansion of Pi.
1

%I #24 Apr 08 2020 00:24:50

%S 6,46,2952,17992,19451,768,1722783,36356650,564665215,20148132320,

%T 27014073315,897831316568,10542036048463,5758910552723

%N Index of the n-th 9 in the first occurrence of a string of exactly n 9's in the decimal expansion of Pi.

%C A048940 is 5, 44, 762, 762, 762, 762, 1722776, 36356642, 564665206, ... - _Alonso del Arte_, Mar 25 2015

%H Dave Andersen, <a href="http://www.angio.net/pi/">The Pi-Search Page</a>.

%F a(n) = A096763(n) + n. - _Danny Rorabaugh_, Mar 31 2015

%o (PARI) { default(realprecision, 20080); for (m = 1, 10, x = Pi; r = 0; for (n = 1, 20000, d = floor(x); x = (x-d)*10; if(d <> 9, if (r <> m, r = 0, print1(n-1, ", "); r = 0; break), r = r + 1)))}

%Y Cf. A048940, A096763, A256109.

%K nonn,base,more

%O 1,1

%A _Kival Ngaokrajang_, Mar 16 2015

%E a(10)-a(14) added using A096763 by _Jinyuan Wang_, Mar 30 2020