cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A334754 The size of partitions of the decimal digits of Pi, starting directly after the decimal point, such that each partition contains the maximum number of digits possible while also avoiding any repeated digits. A digit must be in a partition if the current partition does not contain the current digit.

Original entry on oeis.org

2, 5, 2, 4, 3, 5, 3, 2, 6, 2, 5, 4, 1, 6, 7, 2, 10, 5, 5, 4, 4, 5, 2, 4, 6, 2, 6, 5, 7, 1, 5, 2, 3, 4, 3, 7, 2, 2, 1, 7, 5, 7, 1, 3, 1, 4, 3, 4, 3, 3, 6, 3, 7, 4, 2, 5, 4, 4, 4, 7, 4, 3, 5, 4, 5, 5, 5, 4, 6, 2, 5, 6, 5, 5, 2, 2, 2, 4, 2, 4, 1, 6, 4
Offset: 1

Views

Author

Ryan Brooks, May 10 2020

Keywords

Comments

Assuming digits are random, the expected value for the size of the partitions is 3.66021568 = Sum_{k=1..10} k^2*9!/(10^k*(10-k)!).

Examples

			Pi=3.1415926535897932384626433... => ignore lead 3 and partition as such: 0.|14|15926|53|5897|932|38462|643|3... => 2,5,2,4,3,5,3,...
		

Crossrefs

Cf. A000796 (Pi). Essentially the same as A104807.

Programs

  • PARI
    F(v)={my(L=List(), S=Set()); for(i=1, #v, if(setsearch(S, v[i]), listput(L,#S); S=Set()); S=setunion(S,[v[i]])); Vec(L)}
    { localprec(10^3); my(t=Pi-3); F(digits(floor(t*10^precision(t)))) } \\ Andrew Howroyd, Aug 10 2020