

A086650


nth composite number raised to the nth prime number.


3



16, 216, 32768, 4782969, 100000000000, 106993205379072, 30491346729331195904, 22168378200531005859375, 4951760157141521099596496896, 2528731089327963353099650821015994368
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OFFSET

1,1


COMMENTS

This sequence arises as a result of exponentiation using the terms of the sequence A002808 as the base and the terms of the sequence A000040 as the exponent. This sequence has the very special and rare property of double exponential growth, meaning that its rate of growth grows. This property is due to the unregular growth of the prime exponent in the generating function for this sequence.


LINKS



FORMULA



EXAMPLE

a(3)=8^5=32768 because 8 is the 3rd composite number and 5 is the 3rd prime number.


MATHEMATICA

Select[ Rest[ Range[ 18]], !PrimeQ[ # ] &]^Prime[ Range[18  PrimePi[18]  1]] (* Robert G. Wilson v, Oct 21 2005 *)
Module[{c=Select[Range[20], CompositeQ]}, #[[1]]^#[[2]]&/@Thread[ {c, Prime[ Range[ Length[c]]]}]] (* Harvey P. Dale, Apr 05 2019 *)


CROSSREFS



KEYWORD

easy,nonn


AUTHOR

Christopher M. Tomaszewski (cmt1288(AT)comcast.net), Jul 26 2003


STATUS

approved



