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 A076442 Odd-digit perfect powers. 2
 1, 9, 1331, 3375, 35937, 59319, 357911, 753571, 759375, 5177717, 5359375, 5735339, 9393931, 17373979, 37595375, 39135393, 37159393753, 99317171591, 175333911173, 397551775977, 1913551573375, 9735913353977, 11997979755957, 17171515157399, 335571975137771 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(19) > 1.3*10^11. - Robert G. Wilson v, Dec 17 2002 LINKS Giovanni Resta, Table of n, a(n) for n = 1..566 (terms < 10^57) MATHEMATICA NextOddNbr[n_] := Block[{d = If[ EvenQ[n], IntegerDigits[n + 1], IntegerDigits[n + 2]], l}, l = Length[d]; While[l != 1, If[ EvenQ[ d[[l]]], d[[l]]++ ]; If[d[[l]] > 9, d[[l - 1]]++; d[[l]] = 1]; l-- ]; If[ EvenQ[ d[[1]]], d[[1]]++ ]; If[ d[[1]] > 9, d[[1]] = 11]; FromDigits[d]] k = 1; Do[ If[ !PrimeQ[k] && Apply[GCD, Last[ Transpose[ FactorInteger[k]]]] > 1, Print[k]]; k = NextOddNbr[k], {n, 1, 10^8}] CROSSREFS Cf. A001597, A014261, A075787. Sequence in context: A276823 A020261 A266864 * A076704 A117053 A270067 Adjacent sequences:  A076439 A076440 A076441 * A076443 A076444 A076445 KEYWORD nonn,base AUTHOR Robert G. Wilson v and Zak Seidov, Oct 11 2002 EXTENSIONS Extended by Robert G. Wilson v, Dec 17 2002 Terms a(19) and beyond from Giovanni Resta, Mar 13 2020 STATUS approved

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Last modified October 20 21:32 EDT 2020. Contains 337910 sequences. (Running on oeis4.)