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A119729
a(1)=4, then a(n) is the smallest semiprime not occurring earlier, not ending with zero and starting with the last digit of a(n-1).
1
4, 46, 6, 62, 21, 14, 49, 9, 91, 15, 51, 106, 65, 55, 57, 74, 403, 33, 34, 407, 77, 703, 35, 58, 82, 22, 25, 501, 111, 115, 502, 26, 69, 93, 38, 85, 505, 511, 118, 86, 611, 119, 94, 411, 121, 122, 201, 123, 39, 95, 514, 413, 301, 129, 901, 133, 302, 202, 203, 303, 305
OFFSET
1,1
LINKS
David A. Corneth, Table of n, a(n) for n = 1..10000 (first 1000 terms from Zak Seidov)
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Jonathan Vos Post, Jun 14 2006
STATUS
approved