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%I #36 May 22 2019 06:26:37
%S 2,5,10,3,14,1,18,37,14,43,12,49,8,51,4,57,116,55,122,51,124,45,128,
%T 39,136,35,138,31,140,27,154,23,160,21,170,19,176,13,180,7,186,5,196,
%U 3,200,1,212,435,208,437,204,443,202,453,196,459,190,461,184
%N a(n) = c(1)p(1) + ... + c(n)p(n), where c(i) = 1 if a(i-1) <= p(i) and c(i) = -1 if a(i-1) > p(i), for i = 1,...,n (p(i) = primes).
%C a(n) <= 2*prime(n). Conjecture: every number occurs in the sequence at most finitely many times. - _Thomas Ordowski_, Dec 03 2016
%H Reinhard Zumkeller, <a href="/A022831/b022831.txt">Table of n, a(n) for n = 1..10000</a>
%H <a href="/index/Rea#Recaman">Index entries for sequences related to Recamán's sequence</a>
%e a(1)=2, a(2)=2+3=5, a(3)=5+5=10, a(4)=10-7=3, a(5)=3+11=14, a(6)=14-13=1, ...
%o (Haskell)
%o a022831 n = a022831_list !! n
%o a022831_list = 2 : f 2 (tail a000040_list) where
%o f x (p:ps) | x' > 0 = x' : f x' ps
%o | otherwise = xp : f xp ps where x' = x - p; xp = x + p
%o -- _Reinhard Zumkeller_, Apr 26 2012
%Y Cf. A064365.
%K nonn
%O 1,1
%A _Clark Kimberling_
%E Name corrected by _Sean A. Irvine_, May 22 2019
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