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Search: id:A133048
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| A133048 |
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Powerback(n): reverse the decimal expansion of n, drop any leading zeros, then apply the powertrain map of A133500 to the resulting number. |
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+0
8
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| 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 2, 1, 4, 9, 16, 25, 36, 49, 64, 81, 3, 1, 8, 27, 64, 125, 216, 343, 512, 729, 4, 1, 16, 81, 256, 625, 1296, 2401, 4096, 6561, 5, 1, 32, 243, 1024, 3125, 7776, 16807, 32768, 59049, 6, 1, 64, 729, 4096, 15625, 46656, 117649
(list; graph; listen)
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OFFSET
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0,3
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LINKS
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N. J. A. Sloane, Table of n, a(n) for n = 0..10000
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EXAMPLE
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E.g. 240 -> (0)42 -> 4^2 = 16; 12345 -> 54321 -> 5^4*3^2*1 = 5625.
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MAPLE
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powerback:=proc(n) local a, i, j, t1, t2, t3;
if n = 0 then RETURN(0); fi;
t1:=convert(n, base, 10); t2:=nops(t1);
for i from 1 to t2 do if t1[i] > 0 then break; fi; od:
a:=1; t3:=t2-i+1;
for j from 0 to floor(t3/2)-1 do a := a*t1[i+2*j]^t1[i+2*j+1]; od:
if t3 mod 2 = 1 then a:=a*t1[t2]; fi;
RETURN(a); end;
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CROSSREFS
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Cf. A131571 (fixed points), A133059 and A133134 (records); A133500 (powertrain).
Cf. A133144 (length of trajectory), A031346 and A003001 (persistence).
Adjacent sequences: A133045 A133046 A133047 this_sequence A133049 A133050 A133051
Sequence in context: A004427 A113230 A065881 this_sequence A054055 A067456 A052429
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KEYWORD
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nonn,base
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AUTHOR
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J. H. Conway and njas, Dec 31 2007
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