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%I #18 Oct 23 2021 10:17:54
%S 10,23,41,59,83,109,131,159,187,211,235,269,301,319,349,395,425,457,
%T 487,519,551,581,607,661,689,713,749,789,817,841,883,931,961,1015,
%U 1049,1079,1119,1151,1187,1229,1271,1303,1331,1367,1391,1433,1477,1511,1553,1611
%N a(n) = prime(2n-1) + prime(2n) + prime(2n+1).
%C Original name was: Sum of staircase primes according to the rule: bottom + top + next top.
%H G. C. Greubel, <a href="/A135277/b135277.txt">Table of n, a(n) for n = 1..1000</a>
%F We list the primes in staircase fashion as in A135274. The right diagonal, RD(n), is the set of top primes and the left diagonal, LD(n), is the set of bottom primes. Then a(n) = LD(n+1) + RD(n) + RD(n+2).
%F a(n) = A034961(2*n-1). - _R. J. Mathar_, Sep 10 2016
%t Table[Prime[n + 1] + Prime[n] + Prime[n + 2], {n, 1, 50}][[;; ;; 2]] (* _G. C. Greubel_, Oct 08 2016 *)
%o (PARI) g(n) = forstep(x=1,n,2,y=prime(x+1) + prime(x) + prime(x+2);print1(y","))
%o (PARI) a(n) = prime(2*n-1) + prime(2*n) + prime(2*n+1) \\ _Charles R Greathouse IV_, Oct 08 2016
%o (Python)
%o from sympy import prime
%o def a(n): return prime(2*n-1) + prime(2*n) + prime(2*n+1)
%o print([a(n) for n in range(1, 51)]) # _Michael S. Branicky_, Oct 23 2021
%Y Cf. A034961, A135274.
%K nonn,easy
%O 1,1
%A _Cino Hilliard_, Dec 02 2007
%E New name from _Charles R Greathouse IV_, Oct 08 2016
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