(10n+1)(10n+9).
9, 209, 609, 1209, 2009, 3009, 4209, 5609, 7209, 9009, 11009, 13209, 15609, 18209
2 seqfan posts
Thu Jan 1 20:44:56 CET 2009 [seqfan] Re: Christmas joke Sequences?
Thu Jan 1 07:32:55 CET 2009 [seqfan] Re: Christmas joke Sequences?
Index of A-numbers in seqfan: by ascending order
by month
by frequency
by keyword
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