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A073718
Powers of 2 with composite exponents.
2
16, 64, 256, 512, 1024, 4096, 16384, 32768, 65536, 262144, 1048576, 2097152, 4194304, 16777216, 33554432, 67108864, 134217728, 268435456, 1073741824, 4294967296, 8589934592, 17179869184, 34359738368, 68719476736
OFFSET
1,1
FORMULA
a(n) = 2^A002808(n) = A000079(A002808(n)).
Sum_{n>=1} 1/a(n) = A275306. - Amiram Eldar, Aug 11 2020
MATHEMATICA
Table[2^FixedPoint[n+PrimePi[ # ]+1&, n], {n, 1, 30}]
PROG
(PARI) for(n=4, 100, if(!isprime(n), print1(2^n", "))) \\ Charles R Greathouse IV, Apr 09 2012
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Labos Elemer, Aug 05 2002
STATUS
approved