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A159978
a(n) = (smallest prime > Fibonacci(n)) - Fibonacci(n).
3
1, 1, 1, 2, 2, 3, 4, 2, 3, 4, 8, 5, 6, 2, 3, 4, 4, 7, 20, 14, 3, 2, 4, 13, 4, 10, 11, 16, 14, 23, 4, 4, 25, 10, 14, 35, 6, 24, 3, 2, 6, 7, 12, 20, 9, 48, 10, 5, 28, 18, 23, 14, 14, 11, 16, 10, 21, 4, 62, 13, 38, 12, 7, 16, 12, 19, 36, 28, 143, 32, 58, 29, 96, 100, 33, 2, 30, 27, 12, 62, 25
OFFSET
1,4
FORMULA
a(n) = A013632(A000045(n)). - R. J. Mathar, Apr 29 2009
EXAMPLE
a(6)=3 because the 6th Fibonacci term is 8 and the distance to nextprime(6) is 3 (11-8=3).
MAPLE
A159978 := proc(n) local f; f := combinat[fibonacci](n) ; nextprime(f)-f ; end: seq(A159978(n), n=1..100) ; # R. J. Mathar, Apr 29 2009
MATHEMATICA
Table[f = Fibonacci[n]; NextPrime[f] - f, {n, 200}] (* Vladimir Joseph Stephan Orlovsky, Jul 08 2011 *)
PROG
(UBASIC) 10 'FiboB 20 A=1:print A; 30 B=1:print B; 40 C=A+B:print C; :T=T+1:print "<"; nxtprm(C)-C; ">"; 50 D=B+C:print D; :print "<"; nxtprm(D)-D; ">"; 60 A=C:B=D:if T>22 then stop:else 40
(PARI) a(n) = my(f=fibonacci(n)); nextprime(f+1) - f; \\ Michel Marcus, Sep 22 2022
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Enoch Haga, Apr 28 2009
EXTENSIONS
Extended by R. J. Mathar, Apr 29 2009
STATUS
approved