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A075812
Palindromic odd numbers with exactly 2 prime factors (counted with multiplicity).
1
9, 33, 55, 77, 111, 121, 141, 161, 303, 323, 393, 505, 515, 535, 545, 565, 707, 717, 737, 767, 939, 949, 959, 979, 989, 1111, 1441, 1661, 1991, 3113, 3223, 3443, 3883, 7117, 7447, 7997, 9119, 9229, 9449, 10001, 10201, 10401, 10801, 10901, 11111
OFFSET
1,1
COMMENTS
Odd subsequence of A046328 Palindromes with exactly 2 prime factors (counted with multiplicity). - Zak Seidov, Feb 20 2011
EXAMPLE
9=3^2, 33=3*11 and 55=5*11 are palindromic, odd and are products of exactly 2 prime factors.
MAPLE
test := proc(n) local d; d := convert(n, base, 10); return ListTools[Reverse](d)=d and numtheory[bigomega](n)=2; end; a := []; for n from 1 to 14000 by 2 do if test(n) then a := [op(a), n]; end; od; a;
CROSSREFS
Sequence in context: A111351 A065064 A337234 * A256868 A146262 A161430
KEYWORD
nonn,base
AUTHOR
Jani Melik, Oct 13 2002
EXTENSIONS
Edited by Dean Hickerson, Oct 21 2002
STATUS
approved