|
Search: id:A131536
|
|
|
| A131536 |
|
Least power of 2 having exactly n consecutive 2's in its decimal representation. |
|
+0
1
|
|
| 1, 51, 43, 692, 314, 2354, 8555, 13326, 81784, 279272
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
EXAMPLE
|
a(3)=43 because 2^43(i.e. 8796093022208) is the smallest power of 2 to contain a run of 3 consecutive twos in its decimal form.
|
|
MATHEMATICA
|
a = ""; Do[ a = StringJoin[a, "2"]; b = StringJoin[a, "2"]; k = 1; While[ StringPosition[ ToString[2^k], a] == {} || StringPosition[ ToString[2^k], b] != {}, k++ ]; Print[k], {n, 1, 10} ]
|
|
CROSSREFS
|
Sequence in context: A111402 A087408 A033371 this_sequence A003912 A039932 A031959
Adjacent sequences: A131533 A131534 A131535 this_sequence A131537 A131538 A131539
|
|
KEYWORD
|
more,nonn,base
|
|
AUTHOR
|
Shyam Sunder Gupta (guptass(AT)rediffmail.com), Aug 26 2007
|
|
|
Search completed in 0.002 seconds
|
