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%I #9 Feb 10 2016 15:45:46
%S 0,2,4,8,10,16,18,23,28,32,37,48,63,66,73,76,79,82,99,100,102,106,109,
%T 126,142,147,169,172,177,178,189,190,198,201,205,208,217,225,226,228,
%U 232,235,244,253,258,264,268,278,288,306,333,336,343,348,352,358,361,370,379,382
%N Records in A268630 (= a(n)^2+a(n+1) is prime).
%C See A268496 for the corresponding indices, A268494-A268495 for "late birds". We use offset 0 here because the first term has a special status (it's not really "late") and also because all related sequences (A268630 and A268494 - A268497) have a(0)=0 and omitting this term yields the corresponding "positive integer" variant.
%o (PARI) show(n, f="/tmp/b268497.txt", c=0, a=0, u=[a-1])={for(n=1, n, a>=u[#u]&&if(f, write(f, c++-1, " "a), print1(a", ")); u=setunion(u, [a]); while(#u>1&&u[2]==u[1]+1, u=u[^1]); for(k=u[1]+1, 9e9, !setsearch(u, k) && isprime(a*a+k) && (a=k) && break))}
%K nonn
%O 0,2
%A _M. F. Hasler_, Feb 09 2016