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%I #12 Feb 04 2020 17:14:47
%S 0,3,1,1,5,1,1,1,1,1,3,1,5,7,1,1,7,3,1,5,5,1,1,5,1,7,1,7,1,1,5,1,1,5,
%T 7,3,11,1,7,1,7,1,5,7,1,9,5,7,1,1,7,7,7,1,1,9,1,9,5,5,1,1,1,7,1,5,5,7,
%U 5,7,7,1,3,5,7,1,1,11,1,1,13,1,13,5,1,15,1,1,5,7,1,1,5,1,7,1,1,5,5,3,5,3,19
%N a(n) satisfies P(n) + P(n+1) + a(n) = least prime >= P(n) + P(n+1), where P(i)=i-th prime.
%C a(n) = 1 iff prime(n) is in A177017. - _Robert Israel_, Feb 04 2020
%H Robert Israel, <a href="/A098084/b098084.txt">Table of n, a(n) for n = 1..10000</a>
%e P(1) + P(2) = 2 + 3 = 5; least prime >= 5 = 5, so a(1)=0.
%e P(2) + P(3) = 3 + 5 = 8; least prime > 8 = 11, so a(2) = 11 - 8 = 3.
%e P(3) + P(4) = 5 + 7 = 12; least prime > 12 = 13, so a(3) = 13 - 12 = 1.
%p P:= [seq(ithprime(i),i=1..200)]:
%p map(t -> nextprime(t-1)-t,P[1..-2]+P[2..-1]); # _Robert Israel_, Feb 04 2020
%t f[n_] := Block[{k = 0, p = Prime[n] + Prime[n + 1]}, While[ !PrimeQ[p + k], k++ ]; k]; Table[ f[n], {n, 103}] (* _Robert G. Wilson v_, Sep 24 2004 *)
%Y The primes are in A098085.
%Y Cf. A177017.
%K easy,nonn
%O 1,2
%A _Pierre CAMI_, Sep 13 2004
%E More terms from _Robert G. Wilson v_, Sep 25 2004