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 A121760 In decimal number system, take negative power of 10 at odd digits of n. Sequence gives numerators of result. 2
 1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 11, 21, 31, 41, 51, 61, 71, 81, 91, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 3, 13, 23, 33, 43, 53, 63, 73, 83, 93, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 7, 17, 27, 37, 47, 57, 67 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS See accompanying sequence A121761 In decimal number system, take negative power of 10 at even digits of n. LINKS Zak Seidov, First 1000 terms FORMULA If n = sum(d(i)*10^(i-1)), then a(n)=sum(d(i)*10^((-1)^(1+d(i))*(i-1))). EXAMPLE a(12)=21 because 12=1*10^1+2*10^0 and a(12)=numerator[1*10^((-1)^(1)*1)+2*10^((-1)^(0)*0)=1/10+2=21/10]=21. CROSSREFS Cf. A121761. Sequence in context: A161594 A084011 A004086 * A061816 A083960 A138795 Adjacent sequences:  A121757 A121758 A121759 * A121761 A121762 A121763 KEYWORD base,frac,nonn AUTHOR Zak Seidov, Aug 20 2006 EXTENSIONS a(40) corrected by N. J. A. Sloane, Aug 23 2006 STATUS approved

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Last modified April 10 19:06 EDT 2021. Contains 342853 sequences. (Running on oeis4.)