OFFSET
0,3
COMMENTS
This sequence is infinite because the square root of 100^k - 1 starts with 2*k odd digits.
LINKS
Giovanni Resta, Table of n, a(n) for n = 0..59
EXAMPLE
a(4) = 63 because sqrt(63) = 7.9372539... starts with 4 odd digits.
PROG
(PARI) a(n) = {my(g=10^(n-1), v); for(k=1, oo, if(setintersect([1, 3, 5, 7, 9], v=Set(digits(floor(sqrt(k)*g))[1..n]))==v, return(k))); } \\ Jinyuan Wang, Apr 16 2020
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Jinyuan Wang, Apr 16 2020
EXTENSIONS
Corrected a(31) and more terms from Bert Dobbelaere, Apr 17 2020
STATUS
approved