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A076777
Number of primes between successive Fibonacci numbers inclusive.
4
0, 0, 1, 1, 1, 1, 2, 2, 3, 5, 8, 10, 17, 23, 37, 55, 85, 125, 198, 297, 458, 704, 1088, 1673, 2602, 4029, 6263, 9738, 15187, 23704, 36981, 57909, 90550, 142033, 222855, 349862, 549903, 865019, 1361581, 2145191, 3381318, 5334509, 8419528, 13298630, 21014892, 33227992
OFFSET
0,7
COMMENTS
a(n) = #{p prime | A000045(n)<p<=A000045(n+1)}.
LINKS
Amiram Eldar, Table of n, a(n) for n = 0..122 (calculated using the b-file at A054782)
FORMULA
a(n) = A000720(A000045(n+1)) - A000720(A000045(n)).
EXAMPLE
a(10) = 8, as there are 8 primes greater than A000045(10) = 55 and not greater than A000045(10+1) = 89: 59, 61, 67, 71, 73, 79, 83 and 89.
MAPLE
with(combinat): with(numtheory): seq(pi(fibonacci(n+1))-pi(fibonacci(n)), n=0..35); # Emeric Deutsch
MATHEMATICA
Table[PrimePi[Fibonacci[k+1]]-PrimePi[Fibonacci[k]], {k, 50}] (* Vladimir Joseph Stephan Orlovsky, Nov 30 2010 *)
PROG
(PARI) A076777(n) = primepi(fibonacci(n+1))-primepi(fibonacci(n))
A076777(n) = sum(i=fibonacci(n)+1, fibonacci(n+1), isprime(i)) \\ Michael B. Porter, Nov 24 2009
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Nov 14 2002
EXTENSIONS
More terms from Emeric Deutsch, Mar 02 2005
More terms from Amiram Eldar, Oct 07 2021
STATUS
approved