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A173928 a(n+2)=A162488(n)-A162489(n) where a(1)=0 and a(2)=1. 0
0, 1, 1, 7, 13, 19, 19, 17, 31, 5, 47, 53, 47, 61, 41, 67, 1, 31, 47, 113, 103, 79, 113, 27, 73, 149, 155, 57, 139, 21, 37, 161, 227, 211, 211, 1, 337, 245, 41, 117, 413, 241, 337, 13, 79, 451, 421, 47, 181, 511, 311, 323, 423, 299, 545, 269, 565, 211 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Where A162488 are numbers x such that x^y+y^x is prime, for some y>1, y<x and A162489 is least y such that x^y+y^x is prime, for x=A162488(n).

LINKS

Table of n, a(n) for n=1..58.

EXAMPLE

a(1)=0 because 1^1+1^1=2=prime and 0=1-1; a(2)=1 because 1^2+2^1=3=prime and 1=2-1; a(3)=1 because 2^3+3^2 and 1=3-2; a(4)=7 because 2^9+9^2 and 7=9-2.

CROSSREFS

Cf. A094133, A162488, A162489.

Sequence in context: A107744 A254762 A275681 * A304995 A160007 A024613

Adjacent sequences:  A173925 A173926 A173927 * A173929 A173930 A173931

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Mar 02 2010

EXTENSIONS

a(30) and a(32) corrected by R. J. Mathar, Mar 09 2010

STATUS

approved

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Last modified July 22 15:23 EDT 2019. Contains 325224 sequences. (Running on oeis4.)