

A080035


"Orderly" Friedman numbers (or "good" Friedman numbers): Friedman numbers (A036057) where the construction digits are used in the proper order.


7



127, 343, 736, 1285, 2187, 2502, 2592, 2737, 3125, 3685, 3864, 3972, 4096, 6455, 11264, 11664, 12850, 13825, 14641, 15552, 15585, 15612, 15613, 15617, 15618, 15621, 15622, 15623, 15624, 15626, 15632, 15633, 15642, 15645, 15655, 15656
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OFFSET

1,1


COMMENTS

Primes in this sequence are listed in A252483. The subsequence A156954 is a "simplified" variant where no parentheses, unary operations (negation) nor concatenation is allowed.  M. F. Hasler, Jan 07 2015


REFERENCES

Credit goes to Mike Reid (Brown University) and Eric Friedman (Stetson University).
Colin Rose, "Radical Narcissistic numbers", J. Recreational Mathematics, vol. 33, (20042005), pp. 250254. See page 251.


LINKS

Table of n, a(n) for n=1..36.
M. Brand, Friedman numbers have density 1, Discrete Applied Mathematics, Volume 161, Issues 1617, November 2013, Pages 23892395.
Ed Copeland and Brady Haran, Friedman numbers  Numberphile, 2014
Eric Friedman, Friedman Numbers.
Robert G. Wilson v, Table of n, a(n) for n = 1..108 .


EXAMPLE

127 = 1 + 2^7, 343 = (3 + 4) ^ 3, 736 = 7 + 3^6, etc.
The 4th "orderly" Freidman number is 1285 = (1 + 2^8) * 5.


CROSSREFS

Cf. A036057.
Sequence in context: A157949 A142165 A031933 * A162004 A112419 A142201
Adjacent sequences: A080032 A080033 A080034 * A080036 A080037 A080038


KEYWORD

nonn,base,nice


AUTHOR

David Rattner (david_rattner(AT)prusec.com), Mar 14 2003


EXTENSIONS

More terms from Alonso del Arte, Aug 25 2004
Edited by M. F. Hasler, Jan 07 2015


STATUS

approved



