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 A121260 Beginning with a(1)=0, take a(n) to be the smallest number not equal to the product of two consecutive (not distinct) earlier terms. 0
 0, 0, 1, 1, 2, 2, 3, 3, 5, 5, 7, 7, 8, 8, 10, 10, 11, 11, 12, 12, 13, 13, 14, 14, 16, 16, 17, 17, 18, 18, 19, 19, 20, 20, 21, 21, 22, 22, 23, 23, 24, 24, 26, 26, 27, 27, 28, 28, 29, 29, 30, 30, 31, 31, 32, 32, 33, 33, 34, 34, 36, 36, 37, 37, 38, 38, 39, 39, 40, 40, 41, 41, 42, 42 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 COMMENTS Apparently the definition is: a(1)=0. For even n, a(n)=a(n-1). For odd n, a(n) is the smallest value > a(n-1) which is not equal to some product a(i)*a(i-1) of two consecutive earlier terms. - R. J. Mathar, Jun 21 2021 LINKS CROSSREFS Cf. A121229. Sequence in context: A341462 A035031 A035032 * A121261 A085885 A309685 Adjacent sequences:  A121257 A121258 A121259 * A121261 A121262 A121263 KEYWORD easy,nonn AUTHOR Giovanni Teofilatto, Aug 23 2006 EXTENSIONS Offset corrected. - R. J. Mathar, Jun 20 2021 STATUS approved

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Last modified September 16 08:18 EDT 2021. Contains 347469 sequences. (Running on oeis4.)