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URL: https://oeis.org/A109212

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A109212
In the decimal expansion of Pi, lengths of subsequences with sum = 100.
2
20, 22, 18, 18, 19, 19, 19, 22, 22, 22, 20, 19, 21, 21, 21, 22, 25, 22, 24, 23, 24, 24, 23, 23, 25, 24, 26, 25, 25, 26, 27, 27, 26, 29, 29, 26, 27, 26, 26, 25, 24, 21, 21, 20, 19, 20, 20, 20, 20, 20, 20, 20, 19, 21, 24, 23, 23, 23, 23, 22, 21, 23, 23, 25, 26, 26, 25, 26, 26
OFFSET
1,1
COMMENTS
Average length is about 100/4.5=22.22 because average decimal digit is about 4.5.
FORMULA
a(n) = A109211(n) - A109210(n) + 1.
PROG
(PARI) default(realprecision, 101000); v=digits(floor(Pi*10^10^5));
lista(nn) = {my(x=21, s=103); for(k=2, nn, s-=v[k-1]; if(s==100, print1(x-k+1, ", "), while(s<100, s+=v[x++]); if(s==100, print1(x-k+1, ", ")))); } \\ Jinyuan Wang, Mar 22 2020
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Zak Seidov, Jun 22 2005
STATUS
approved