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 A059402 Numbers with more than one prime factor that do not end in 0 and contain as substrings every maximal prime power dividing them. 2
 1197, 14673, 83731, 129717, 167835, 322794, 429635, 831328, 1127125, 1183497, 1184128, 1319825, 1344837, 1371294, 1724786, 1731195, 1943795, 2597175, 2971137, 2993715, 3161907, 3181437, 3719193, 4609731, 4913928, 5037365, 5912739, 5981125, 6193563 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Reinhard Zumkeller and Donovan Johnson, Table of n, a(n) for n = 1..500 (first 100 terms from Reinhard Zumkeller) Reinhard Zumkeller, Demonstration of first 100 terms EXAMPLE 1197 = 9 * 7 * 19 and all of these are substrings. MATHEMATICA ok[n_] := If[id = IntegerDigits[n]; Last[id] == 0, False, If[ff = IntegerDigits /@ Apply[ Power, FactorInteger[n], {1}]; Length[ff] == 1, False, And @@ (MatchQ[id, {___, Sequence @@ #, ___}] & ) /@ ff]]; A059402 = {}; Do[ If[ok[n], Print[n]; AppendTo[A059402, n]], {n, 1, 6*10^6}] (* Jean-François Alcover, Nov 24 2011 *) PROG (Haskell) import Data.List (isInfixOf) a059402 n = a059402_list !! (n-1) a059402_list = filter chi [1..] where chi n = n `mod` 10 > 0 && f n 1 0 a000040_list where f :: Integer -> Integer -> Int -> [Integer] -> Bool f 1 1 o _ = o > 1 f m x o ps'@(p:ps) | r == 0 = f m' (p*x) o ps' | x > 1 = show x `isInfixOf` show n && f m 1 (o+1) ps | m < p * p = f 1 m o ps | otherwise = f m 1 o ps where (m', r) = divMod m p -- Reinhard Zumkeller, Jul 21 2011 (Python) from sympy import factorint A059402_list = [n for n in range(2, 10**6) if n % 10 and len(factorint(n)) > 1 and all(str(a**b) in str(n) for a, b in factorint(n).items())] # Chai Wah Wu, Aug 13 2021 CROSSREFS Sequence in context: A096955 A113898 A059401 * A252000 A251993 A250379 Adjacent sequences: A059399 A059400 A059401 * A059403 A059404 A059405 KEYWORD base,nice,nonn AUTHOR Erich Friedman, Jan 29 2001 EXTENSIONS Offset corrected and a(6)-a(26) from Donovan Johnson, Jul 09 2010 Definition stated more precisely by Reinhard Zumkeller, Jul 19 2011 STATUS approved

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Last modified October 3 19:07 EDT 2023. Contains 365870 sequences. (Running on oeis4.)