|
|
A048349
|
|
a(n)^2 is the smallest square containing exactly n 4's.
|
|
1
|
|
|
2, 12, 38, 212, 2538, 6888, 66592, 210771, 2059962, 6696592, 21081538, 209868112, 664488107, 3800598038, 18613286762, 209820981888, 666669703412, 666516649788, 6666894662768, 49400874945738
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
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_] := Block[{k=1}, While[DigitCount[k^2, 10, 4] != n, k++]; k]; Array[a, 7] (* Giovanni Resta, Jul 27 2018 *)
|
|
CROSSREFS
|
Cf. A036511, A034984.
Sequence in context: A035597 A000913 A026575 * A009632 A190022 A086602
Adjacent sequences: A048346 A048347 A048348 * A048350 A048351 A048352
|
|
KEYWORD
|
nonn,base,more
|
|
AUTHOR
|
Patrick De Geest, Mar 15 1999
|
|
EXTENSIONS
|
More terms from Jon E. Schoenfield, Jan 14 2009
a(17)-a(20) from Giovanni Resta, Jul 27 2018
|
|
STATUS
|
approved
|
|
|
|