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%I #26 Aug 04 2022 05:51:57
%S 1,1,2,1,2,1,2,3,4,1,2,1,2,3,4,1,2,1,2,3,4,1,2,3,4,5,6,1,2,1,2,3,4,5,
%T 6,1,2,3,4,1,2,1,2,3,4,1,2,3,4,5,6,1,2,3,4,5,6,1,2,1,2,3,4,5,6,1,2,3,
%U 4,1,2,1,2,3,4,5,6,1,2,3,4,1,2,3,4,5,6,1,2,3,4,5,6
%N a(n) = n - prevprime(n).
%C All runs end in even numbers at a(p), new highs are found at A000101 and the increasing gap size is A005250. - _Robert G. Wilson v_, Dec 07 2001
%C All terms are positive since here the variant 2 (A151799(n) < n) of the prevprime function is used, rather than the variant 1 (A007917(n) <= n). - _M. F. Hasler_, Sep 09 2015
%F a(n) = A064722(n-1) + 1. - _Pontus von Brömssen_, Jul 31 2022
%p A049711 := n-> n-prevprime(n);
%t PrevPrim[n_] := Block[ {k = n - 1}, While[ !PrimeQ[k], k-- ]; Return[k]]; Table[ n - PrevPrim[n], {n, 3, 100} ]
%t Array[#-NextPrime[#,-1]&,100,3] (* _Harvey P. Dale_, Dec 07 2011 *)
%o (PARI) A049711(n)=n-precprime(n-1) \\ _M. F. Hasler_, Sep 09 2015
%Y Cf. A000101, A005250, A049613, A049653, A049716, A049847, A064722.
%Y Cf. A151799, A007917.
%Y Cf. A175851.
%K nonn
%O 3,3
%A _N. J. A. Sloane_
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