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A226032
Numbers of the form xyz, where x and z have the same number of digits and x*z = y.
1
100, 111, 122, 133, 144, 155, 166, 177, 188, 199, 200, 221, 242, 263, 284, 300, 331, 362, 393, 400, 441, 482, 500, 551, 600, 661, 700, 771, 800, 881, 900, 991, 2105, 2126, 2147, 2168, 2189, 3124, 3155, 3186, 3217, 3248, 3279, 4123, 4164, 4205, 4246, 4287, 4328
OFFSET
1,1
COMMENTS
The same digit may not be used twice as both an "outer" and "inner" digit. For example, 11211 is not in the sequence, but 1112111 is.
Leading zeros are not allowed.
LINKS
Christian N. K. Anderson, Table of n, a(n) for n = 1..10000
EXAMPLE
482 is in the sequence because 4*2 = 8.
4205 is in the sequence because 4*5 = 20.
100 is in the sequence because 1*0 = 0. However, 1200 is not because even though 12*0 = 0, 12 and 0 do not have the same number of digits. Likewise, 12|0|00 and 12|00|00 are not in the sequence because leading zeros are not allowed.
PROG
(R)
y=c(); for(i in 1:9) for(j in 0:9) y=c(y, as.numeric(paste(i, i*j, j, sep=""))); sort(y)
CROSSREFS
Sequence in context: A066511 A281193 A285776 * A373066 A286699 A171222
KEYWORD
nonn,base
AUTHOR
Alan Wing-lun, Christian N. K. Anderson, Kevin L. Schwartz, May 23 2013
STATUS
approved