A048353 a(n)^2 is the smallest square containing exactly n 8's.

9, 83, 298, 1378, 8878, 29641, 298141, 623609, 9321378, 28072917, 94121667, 329877083, 4341484641, 29478276559, 62360956378, 151284113141, 3436394751609, 9428037062872, 22065558748622, 29770520349641

Offset

1,1

Comments

a(21) > 10^14. - Giovanni Resta, Jul 27 2018

Links

Table of n, a(n) for n=1..20.

Eric Weisstein's World of Mathematics, Square Number

Mathematica

a[n_] := Module[{i = 1}, While[DigitCount[i^2][[8]] != n, i++ ]; i]; (* Sam Handler (sam_5_5_5_0(AT)yahoo.com), Aug 22 2006 *)

Crossrefs

Cf. A036515, A034992.

Sequence in context: A015497 A174472 A039357 * A037502 A037679 A015579

Adjacent sequences: A048350 A048351 A048352 * A048354 A048355 A048356

Keyword

nonn,base,more

Author

Patrick De Geest, Mar 15 1999

Extensions

a(13)-a(16) from Jon E. Schoenfield, Jan 24 2009

a(17)-a(20) from Giovanni Resta, Jul 27 2018

Status

approved