A135251 Maximal number of zero digits in square of number with n digits not divisible by 10.

0, 1, 3, 4, 6, 8, 10

Offset

1,3

Links

Table of n, a(n) for n=1..7.

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, 0, 9}], {s, 0, 9}], {p, 0, 9}], {r, 0, 9}], {q, 0, 9}], {b, 1, 9}]; mx

Crossrefs

Cf. A134843, A134844, A134845, A134846, A134847, A134848, A134849, A135215, A135217, A135219, A135252, A135253.

Sequence in context: A355200 A049433 A250984 * A298809 A335194 A307647

Adjacent sequences: A135248 A135249 A135250 * A135252 A135253 A135254

Keyword

base,nonn

Author

Artur Jasinski, Nov 24 2007

Status

approved