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A046457 Concatenation of the 8 prime factors of composite a(n) is a palindrome. 0

%I

%S 256,6561,390625,2484375,5764801,13361565,25765131,69090879,89994375,

%T 110875779,125919255,128035545,188245551,207847185,210815759,

%U 214358881,242810337,246891183,246944565,272828031,400792119,464794365,475376391

%N Concatenation of the 8 prime factors of composite a(n) is a palindrome.

%e 2484375 = 3 * 5 * 5 * 5 * 5 * 5 * 5 * 53 -> 355555553 is palindromic.

%t 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

%Y Cf. A046447.

%K nonn,base

%O 0,1

%A _Patrick De Geest_, Jul 15 1998

%E More terms from Sam Handler (sam_5_5_5_0(AT)yahoo.com), Aug 17 2006

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Last modified November 28 21:30 EST 2021. Contains 349415 sequences. (Running on oeis4.)