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A088642
If k is a palindrome made of only two nonzero digits a and b then the palindrome arising by swapping the digits a and b.
0
212, 313, 414, 515, 616, 717, 818, 919, 121, 323, 424, 525, 626, 727, 828, 929, 131, 232, 434, 535, 636, 737, 838, 939, 141, 242, 343, 545, 646, 747, 848, 949, 151, 252, 353, 454, 656, 757, 858, 959
OFFSET
1,1
COMMENTS
If a(r) = s then a(s) = r.
EXAMPLE
The term corresponding to 1221221 is 2112112 and vice versa.
CROSSREFS
Sequence in context: A358873 A133651 A093807 * A251126 A078211 A158794
KEYWORD
base,easy,nonn
AUTHOR
Amarnath Murthy, Oct 27 2003
STATUS
approved