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a(1)=1, a(n) = the least positive number not yet in sequence which added to max(a(1)..a(n-1)) gives a prime.
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%I #4 Mar 31 2012 14:40:13

%S 1,2,3,4,7,6,10,9,13,16,15,21,8,20,22,19,25,12,18,28,31,30,36,5,11,17,

%T 23,35,37,24,34,42,29,41,47,14,26,32,50,33,39,51,38,46,52,27,45,49,55,

%U 48,54,58,43,69,40,44,62,68,70,57,61,67,79,60,72,78,84,53,65,73,83,89

%N a(1)=1, a(n) = the least positive number not yet in sequence which added to max(a(1)..a(n-1)) gives a prime.

%C Apparently an arrangement of positive integers. Among the first 1000 terms in the sequence, the first absent numbers are: 809,890,902,908,920,926,932,938,944,945,963,968,977,986,998. Fixed points of the arrangement are: 1,2,3,4,6,61,106,137,419,452,486,557,730.

%H Zak Seidov, <a href="/A125595/b125595.txt">Tableof n, a(n) for n = 1..1000</a>

%e n=7: ss={1,2,3,4,7,6}, max(ss)=7; a(7)=the least positive number d not yet in ss such that max(ss)+d is prime, d=10, 7+10=17, hence a(7)=10.

%K nonn

%O 1,2

%A _Zak Seidov_, Nov 26 2006