|
Search: id:A059307
|
|
|
| A059307 |
|
Numbers n such that base 10 representation of n does not contain a block of digits which is a square: blocks like 0, 1, 4, 9, 36, 121, ... are forbidden. |
|
+0
2
|
|
| 2, 3, 5, 6, 7, 8, 22, 23, 26, 27, 28, 32, 33, 35, 37, 38, 52, 53, 55, 56, 57, 58, 62, 63, 65, 66, 67, 68, 72, 73, 75, 76, 77, 78, 82, 83, 85, 86, 87, 88, 222, 223, 226, 227, 228, 232, 233, 235, 237, 238, 262, 263, 265, 266, 267, 268, 272, 273, 275, 276, 277, 278, 282
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
COMMENT
|
"Squarefree" integers. The usual definition of "squarefree" means that there is no square as divisor, but here we consider numbers without any square in their decimal expansion. Of the first 1000 integers only 232 are in the sequence, while 608 are squarefree in the usual sence. - Zak Seidov (zakseidov(AT)yahoo.com), Sep 26 2002
|
|
EXAMPLE
|
a(7) = 22 because both 2 and 22 are nonsquares.
323 and 326 are members because they have no squares 0, 1, 4, 9, 16, 25, 36... in their decimal expansion; while the two numbers between, 324 and 325, are not members because 324 contains square 4, and 325 - square 25.
|
|
CROSSREFS
|
A subsequence of A000037.
Sequence in context: A039086 A050025 A074492 this_sequence A068938 A039250 A072601
Adjacent sequences: A059304 A059305 A059306 this_sequence A059308 A059309 A059310
|
|
KEYWORD
|
nonn,base
|
|
AUTHOR
|
Noam Katz (noamkj(AT)hotmail.com), Jan 25 2001
|
|
|
Search completed in 0.002 seconds
|
