

A331882


a(n) is the number of digits in the decimal expansion of the fractional part of Pi needed to contain n occurrences of an ndigit substring.


1




OFFSET

1,2


LINKS

Table of n, a(n) for n=1..8.


EXAMPLE

a(1) = 1, because we need 1 digit to have the first 1digit substring ('1') appearing 1 time;
a(2) = 22, because we need 22 digits (1415926535897932384626) to have the first 2digit substring ('26') appearing 2 times;
a(3) is 219, because we need 219 digits (1415....933446) to have the first 3digit substring ('446') appearing 3 times;
and so on.


CROSSREFS

Cf. A000796, A159345, A331881 (the repeated ndigit substrings).
Sequence in context: A224052 A224305 A224369 * A008453 A066573 A290362
Adjacent sequences: A331879 A331880 A331881 * A331883 A331884 A331885


KEYWORD

nonn,base,hard,more


AUTHOR

Stijn Dierckx, Jan 30 2020


STATUS

approved



