%I #9 Feb 22 2023 18:31:35
%S 1,1,1,2,2,3,3,5,5,5,5,8,8,13,13,13,13,21,21,34,34,34,34,55,55,55,55,
%T 55,55,89,89,144,144,144,144,144,144,233,233,233,233,377,377,610,610,
%U 610,610,987,987,987,987,987,987,1597,1597,1597,1597,1597,1597,2584
%N a(n)=a(p)+a(q) where p and q are the two primes less than n and closest to n; with a(1)=1, a(2)=1, a(3) = 1.
%H Robert Israel, <a href="/A059974/b059974.txt">Table of n, a(n) for n = 1..10000</a>
%e a(4)=a(3)+a(2)=1+1=2
%p with(numtheory): a := proc(n) option remember: if n <= 3 and n >=1 then RETURN(1) fi: a(prevprime(n))+ a(prevprime(prevprime(n))): end: for n from 1 to 150 do printf(`%d,`,a(n)) od:
%K easy,nonn
%O 1,4
%A Brian Wallace (wallacebrianedward(AT)yahoo.co.uk), Mar 05 2001
%E More terms from _James A. Sellers_, Mar 15 2001
%E Name edited by _Robert Israel_, Feb 22 2023
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