A034979 Smallest square starting with a string of n 1's.

1, 1156, 111556, 11115556, 111112681, 111111555556, 11111115555556, 1111111155555556, 111111111555555556, 11111111115555555556, 111111111113333185156, 11111111111122500004921, 11111111111115555555555556, 111111111111119590793871025, 11111111111111115805344390916, 11111111111111115805344390916, 111111111111111115889741773581604, 11111111111111111167337156002376484, 11111111111111111115555555555555555556, 1111111111111111111155555555555555555556

Offset: 1

Author

Patrick De Geest, Nov 15 1998

Keywords

• nonn
• base

Links

• Robert Israel, Table of n, a(n) for n = 1..498

Crossrefs

Cf. A034978, A102807.

Programs

Maple

f:= proc(n) local x,k,s;
  x:= (10^n-1)/9;
  for k from 0 do
    s:= ceil(sqrt(10^k*x))^2;
    if s < (x+1)*10^k then return s fi
  od
end proc:
map(f, [$1..20]); # Robert Israel, May 31 2023

Formula

a(n) <= A102807(n). - Robert Israel, May 31 2023

Extensions

More terms from Francisco Salinas (franciscodesalinas(AT)hotmail.com), Dec 23 2001