OFFSET
1,1
COMMENTS
It is natural to conjecture that a(n) ~ 1562500n/567. - Charles R Greathouse IV, May 22 2015
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..10000
FORMULA
a(n) = A280183(n) + 1. - Bobby Jacobs, Jan 03 2017
EXAMPLE
61 is in the sequence because the 10 digits starting at the 61st digit of Pi are 4, 5, 9, 2, 3, 0, 7, 8, 1, 6.
MATHEMATICA
pan[s_, n_]:=Select[Range[Length@s-n+1], Length@ Union@ Take[s, {#, #+n-1}]==n&]; pan[RealDigits[Pi, 10, 10^5][[1]], 10] (* Giovanni Resta, May 22 2015 *)
PROG
(PARI)
default(realprecision, 50080);
infix(v, a, b) = {my(i, s=[]); for(i=a, b, s=concat(s, v[i])); s}
panpi(m) = {
L=List(); p=Pi; for(n=1, 50000, d=floor(p); p=(p-d)*10; listput(L, d)); v=Vec(L);
s=[]; for(k=1, #v-m+1, in=infix(v, k, k+m-1); if(#in==#vecsort(in, , 8), s=concat(s, k))); s
}
panpi(10)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Colin Barker, May 22 2015
EXTENSIONS
a(21)-a(38) from Giovanni Resta, May 22 2015
STATUS
approved