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A073050
a(n) = prime(2^n + 2) - prime(2^n + 1) - 1.
0
1, 1, 5, 1, 1, 3, 5, 5, 3, 3, 9, 11, 5, 21, 1, 3, 23, 1, 31, 15, 17, 17, 15, 91, 9, 13, 9, 41, 43, 7, 97, 69, 7, 35, 7, 23, 5, 19, 63, 5, 35, 25, 21, 29, 29, 9, 117, 29, 3, 85, 119, 35, 37, 127, 9, 51, 5, 9, 47, 33, 49, 83, 83, 19, 41, 5, 17, 95, 3, 29, 29, 401, 25, 143, 19, 27, 65, 57
OFFSET
1,3
COMMENTS
Total sum of the second differences of the primes (A036263) to 2^n.
MATHEMATICA
a[n_] := Prime[2^n+2]-Prime[2^n+1]-1; a/@Range[26]
PROG
(Python)
from sympy import nextprime, prime
def a(n): p = prime(2**n + 1); return nextprime(p) - p - 1
print([a(n) for n in range(1, 25)]) # Michael S. Branicky, Dec 27 2021
CROSSREFS
Sequence in context: A346916 A359667 A010129 * A366426 A154740 A179261
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Aug 15 2002
EXTENSIONS
a(42)-a(47) from Michael S. Branicky, Dec 27 2021
a(48)-a(78) from Michael S. Branicky, Dec 30 2021 using A033844
STATUS
approved