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a(n) = Sum_{k >= 0} prime(n-4k).
1

%I #8 Jun 27 2021 13:48:46

%S 2,3,5,7,13,16,22,26,36,45,53,63,77,88,100,116,136,149,167,187,209,

%T 228,250,276,306,329,353,383,415,442,480,514,552,581,629,665,709,744,

%U 796,838,888,925,987,1031,1085,1124,1198,1254,1312,1353

%N a(n) = Sum_{k >= 0} prime(n-4k).

%H Harvey P. Dale, <a href="/A100111/b100111.txt">Table of n, a(n) for n = 1..1000</a>

%e a(5) = prime(5) + prime(1) = 11 + 2 = 13.

%t Table[Total[Prime[Range[n,1,-4]]],{n,50}] (* _Harvey P. Dale_, Jun 27 2021 *)

%o (PARI) a(n) = if (n<4 || n%4, sum(k=0, n\4, prime(n - 4*k)), sum(k=0, n\4 - 1, prime(n - 4*k))) \\ _Michel Marcus_, Jun 30 2013

%K nonn

%O 1,1

%A _Jorge Coveiro_, Dec 26 2004

%E More terms from _Michel Marcus_, Jun 30 2013