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 A176146 a(n) = n-th-semiprime without last digit. 0
 0, 0, 0, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 4, 4, 5, 5, 5, 5, 6, 6, 6, 7, 7, 8, 8, 8, 8, 9, 9, 9, 9, 10, 11, 11, 11, 11, 12, 12, 12, 12, 13, 13, 14, 14, 14, 14, 14, 15, 15, 15, 16, 16, 16, 17, 17, 18, 18, 18, 19, 20, 20, 20, 20, 20, 20, 21, 21, 21, 21, 21, 21, 22, 22, 23, 23, 24, 24, 25 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,7 COMMENTS Sequence A131109 shows that a(n+1)-a(n) can be larger than 1. [From T. D. Noe, Apr 12 2010] The differences exceed 1 for the first time between a(186) = 59 and a(187) = 61. [R. J. Mathar, Apr 12 2010] LINKS CROSSREFS Cf. A176044, A001358, A106146. Sequence in context: A108956 A289133 A135297 * A171481 A230775 A108037 Adjacent sequences:  A176143 A176144 A176145 * A176147 A176148 A176149 KEYWORD base,easy,nonn AUTHOR Giovanni Teofilatto, Apr 10 2010 STATUS approved

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Last modified September 24 06:13 EDT 2021. Contains 347623 sequences. (Running on oeis4.)