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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 (list; graph; refs; listen; history; text; internal format)
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, (2004-2005), pp. 250-254. 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 16-17, November 2013, Pages 2389-2395.

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

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Last modified July 6 13:59 EDT 2015. Contains 259274 sequences.