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A085607
Non-palindromic n and its digit reversal have the same sum of prime factors (with repetition).
1
45, 54, 250, 495, 594, 1131, 1311, 2262, 2550, 2622, 2750, 2926, 3393, 3933, 4154, 4489, 4514, 4545, 4636, 4995, 5454, 5808, 5994, 6292, 6364, 6550, 7800, 8085, 8749, 9478, 9844, 12441, 13980, 14269, 14421, 15167, 15180, 15602, 16237, 18449, 18977
OFFSET
1,1
LINKS
EXAMPLE
a(3)=250 because 250 = 2*5^3 and 52 = 2^2*13 and 2+5+5+5 = 2+2+13 = 17.
MATHEMATICA
spf[n_]:=Total[Flatten[Table[#[[1]], #[[2]]]&/@FactorInteger[n]]]; spffQ[ n_]:=!PalindromeQ[n]&&spf[n]==spf[IntegerReverse[n]]; Select[Range[ 20000], spffQ] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, May 19 2017 *)
CROSSREFS
Sequence in context: A039423 A043246 A044026 * A087993 A062390 A167328
KEYWORD
base,nonn
AUTHOR
Jason Earls, Jul 08 2003
EXTENSIONS
Corrected by T. D. Noe, Oct 25 2006
STATUS
approved