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A140893
a(n) = prime(n)^prime(n+1) - prime(n+1)^prime(n).
2
-1, 118, 61318, 1957839572, 32730551749894, 8640511341348431996, 233592048827366522661214, 257755012474380136537664158772, 3091054326372819773383775097721670599074, 2141662167055484666186673758527328459608763158
OFFSET
1,2
COMMENTS
a(n) > 0 for n>=2. - Robert Israel, Nov 02 2014
a(n) = A053089(n) - A078422(n). - Michel Marcus, Oct 10 2016
LINKS
EXAMPLE
n=1: a(1) = prime(1)^prime(1+1) - prime(1+1)^prime(1) = 2^3 - 3^2 = 8 - 9 = -1.
n=3: a(3) = prime(3)^prime(4) - prime(4)^prime(3) = 5^7 - 7^5 = 78125 - 16807 = 61318.
MAPLE
seq(ithprime(i)^ithprime(i+1)-ithprime(i+1)^ithprime(i), i=1..20); # Robert Israel, Nov 02 2014
MATHEMATICA
Array[Prime[ # ]^Prime[ #+1]-Prime[ #+1]^Prime[ # ]&, 16] (* Vladimir Joseph Stephan Orlovsky, Oct 11 2009 *)
PROG
(Magma) [NthPrime(n)^NthPrime(n+1)-NthPrime(n+1)^NthPrime(n): n in [1..10]]; // Vincenzo Librandi, Nov 02 2014
CROSSREFS
KEYWORD
sign
AUTHOR
EXTENSIONS
Corrected and extended by Vladimir Joseph Stephan Orlovsky, Oct 11 2009
a(10) from Vincenzo Librandi, Nov 02 2014
STATUS
approved