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 A046457 Concatenation of the 8 prime factors of composite a(n) is a palindrome. 0
 256, 6561, 390625, 2484375, 5764801, 13361565, 25765131, 69090879, 89994375, 110875779, 125919255, 128035545, 188245551, 207847185, 210815759, 214358881, 242810337, 246891183, 246944565, 272828031, 400792119, 464794365, 475376391 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 LINKS EXAMPLE 2484375 = 3 * 5 * 5 * 5 * 5 * 5 * 5 * 53 -> 355555553 is palindromic. MATHEMATICA For[n=2, n<1000000, n++, factors=FactorInteger[n]; If[Total[Transpose[factors][[2]]]!=8, Continue[]]; digits={}; For[i=1, i<=Length[factors], i++, digits=Join[digits, Flatten[Table[IntegerDigits[factors[[i, 1]]], {factors[[i, 2]]}]]]; ]; If[digits==Reverse[digits], Print[n]]; ]; - Sam Handler (sam_5_5_5_0(AT)yahoo.com), Aug 17 2006 CROSSREFS Cf. A046447. Sequence in context: A210840 A001016 A050755 * A179645 A056585 A321818 Adjacent sequences:  A046454 A046455 A046456 * A046458 A046459 A046460 KEYWORD nonn,base AUTHOR Patrick De Geest, Jul 15 1998 EXTENSIONS More terms from Sam Handler (sam_5_5_5_0(AT)yahoo.com), Aug 17 2006 STATUS approved

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Last modified November 25 14:33 EST 2020. Contains 338624 sequences. (Running on oeis4.)