OFFSET
1,1
COMMENTS
It is natural to conjecture that a(n) ~ 156250n/567. - Charles R Greathouse IV, May 22 2015
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..10000
EXAMPLE
63 is in the sequence because the 9 digits starting at the 63rd digit of Pi are 9, 2, 3, 0, 7, 8, 1, 6, 4.
MATHEMATICA
pan[s_, n_]:=Select[Range[Length@s-n+1], Length@ Union@ Take[s, {#, #+n-1}]==n&]; pan[RealDigits[Pi, 10, 10^5][[1]], 9] (* 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(9)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Colin Barker, May 22 2015
STATUS
approved