A135215 Maximal number of zero digits in square of number with n digits and without zero digits.

0, 1, 3, 4, 6, 7, 10, 10, 12, 13, 15

Offset

1,3

Links

Table of n, a(n) for n=1..11.

Mathematica

(*For a(7) *) mx = 0; Do[Do[Do[Do[Do[Do[Do[k = 10^6b + 10^5q + 10^4r + 10^3p + 10^2s + 10n + m; w = IntegerDigits[k^2]; ile = 0; Do[If[w[[t]] == 0, ile = ile + 1; If[ile > mx, mx = ile]], {t, 1, Length[w]}], {m, 1, 9}], {n, 1, 9}], {s, 1, 9}], {p, 1, 9}], {r, 1, 9}], {q, 1, 9}], {b, 1, 9}]; mx

Crossrefs

Cf. A134843, A134844, A134845, A134846, A134847, A134848, A134849.

Sequence in context: A131530 A285379 A102093 * A092494 A274429 A050618

Adjacent sequences: A135212 A135213 A135214 * A135216 A135217 A135218

Keyword

nonn,base

Author

Artur Jasinski, Nov 23 2007

Extensions

a(8)-a(11) from Lars Blomberg, Jun 26 2011

Status

approved