A109212 - OEIS

A109212

In the decimal expansion of Pi, lengths of subsequences with sum = 100.

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

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Average length is about 100/4.5=22.22 because average decimal digit is about 4.5.

LINKS

Table of n, a(n) for n=1..69.

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

Cf. A000796, A109210, A109211.

Sequence in context: A041837 A041838 A128356 * A259742 A050653 A267510

Adjacent sequences: A109209 A109210 A109211 * A109213 A109214 A109215

KEYWORD

base,nonn

AUTHOR

Zak Seidov, Jun 22 2005

STATUS

approved