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A167998
Numbers n with property that first digit of 5*n = last digit of n.
5
19, 21, 31, 42, 52, 63, 73, 84, 94, 105, 115, 126, 136, 147, 157, 168, 178, 189, 199, 201, 211, 221, 231, 241, 251, 261, 271, 281, 291, 301, 311, 321, 331, 341, 351, 361, 371, 381, 391, 402, 412, 422, 432, 442, 452, 462, 472, 482, 492, 502, 512, 522, 532, 542
OFFSET
1,1
LINKS
EXAMPLE
5*19=95, 5*21=105, 5*31=155, 5*42=210, etc.
MATHEMATICA
Reap[Do[If[IntegerDigits[n][[ -1]]==IntegerDigits[5*n][[1]], Sow[n]], {n, 1000}]][[2, 1]]
Select[Range[100], Last[IntegerDigits[#]] == First[IntegerDigits[5 #]] &] (* G. C. Greubel, Jul 03 2016 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Zak Seidov, Nov 16 2009
STATUS
approved