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%I #13 Feb 21 2019 13:50:32
%S 0,1,3,5,10,13,23,27,44,49,77,83,124,131,189,197,274,283,383,393,522,
%T 533,693,705,902,915,1153,1167,1448,1463,1791,1807,2188,2205,2645,
%U 2663,3164,3183,3751,3771,4410,4431,5143,5165,5956,5979,6853,6877,7840,7865
%N Vertex number of a rectangular spiral related to prime numbers. The distances between nearest edges of the spiral that are parallel to the initial edge are the prime numbers, while the distances between nearest edges perpendicular to the initial edge are all one.
%C First differences give A160793. - _Omar E. Pol_, Oct 31 2011
%H Nathaniel Johnston, <a href="/A160792/b160792.txt">Table of n, a(n) for n = 0..5000</a>
%F a(2n) = a(2n-1) + Sum_{j=1..n} prime(j); a(2n+1) = a(2n) + n + 1 for n >= 1. - _Nathaniel Johnston_, Jun 16 2011
%p A160792 := proc(n) option remember: if(n<=1)then return n: fi: if(n mod 2 = 0)then return procname(n-1)+add(ithprime(j),j=1..n/2): fi: return procname(n-1)+ceil(n/2): end: seq(A160792(n),n=0..49); # _Nathaniel Johnston_, Jun 16 2011
%Y Cf. A000040, A160790, A160791, A160793.
%K easy,nonn
%O 0,3
%A _Omar E. Pol_, May 29 2009
%E Terms after a(10) and edited by _Nathaniel Johnston_, Jun 16 2011
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