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A208262
Numbers with all divisors starting and ending with digit 1.
3
1, 11, 101, 121, 131, 151, 181, 191, 1021, 1031, 1051, 1061, 1091, 1111, 1151, 1171, 1181, 1201, 1231, 1291, 1301, 1321, 1331, 1361, 1381, 1441, 1451, 1471, 1481, 1511, 1531, 1571, 1601, 1621, 1661, 1721, 1741, 1801, 1811, 1831, 1861, 1871, 1901, 1931, 1951, 1991
OFFSET
1,2
COMMENTS
Union of A062332 and A208261. Subsequence of A208259 (numbers starting and ending with digit 1).
EXAMPLE
Divisors of 1111: 1, 11, 101, 1111.
MATHEMATICA
Select[Table[n, {n, 2000}], Union[First /@ IntegerDigits[Divisors[#]]] == {1} && Union[Last /@ IntegerDigits[Divisors[#]]] == {1} &] (* Vladimir Joseph Stephan Orlovsky, Feb 26 2012 *)
CROSSREFS
Cf. A062332 (primes starting and ending with digit 1), A208261 (nonprime numbers with all divisors starting and ending with digit 1).
Sequence in context: A176179 A176196 A303570 * A062696 A113654 A066592
KEYWORD
nonn,base
AUTHOR
Jaroslav Krizek, Feb 24 2012
STATUS
approved