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A278166 a(n) = number of integers one more than a prime encountered before reaching 0 when starting from k = ((n+1)^2)-1 and iterating map k -> k - A002828(k).

%I A278166 #11 Nov 14 2016 10:38:04
%S A278166 1,3,3,5,7,9,9,11,12,14,15,18,19,22,23,26,29,31,34,37,42,46,47,51,54,
%T A278166 58,60,64,68,70,74,78,82,85,88,92,95,99,104,109,114,118,122,128,134,
%U A278166 137,140,149,153,158,164,173,177,183,187,191,199,205,210,217,222,231,236,241,248,256,262,273,278,287,291,298,307,316,322,332
%N A278166 a(n) = number of integers one more than a prime encountered before reaching 0 when starting from k = ((n+1)^2)-1 and iterating map k -> k - A002828(k).
%H A278166 Antti Karttunen, <a href="/A278166/b278166.txt">Table of n, a(n) for n = 1..10000</a>
%H A278166 A. Karttunen, <a href="https://oeis.org/plot2a?name1=A278166&amp;name2=A278168&amp;tform1=untransformed&amp;tform2=untransformed&amp;shift=0&amp;radiop1=ratio&amp;drawlines=true">Ratio a(n)/A278168(n) plotted with OEIS Plot 2 tool</a>
%F A278166 a(1) = A277486(1); for n > 1, a(n) = A277486(n) + a(n-1).
%e A278166 For n=4, starting from k = ((4+1)^2)-1, and iterating k -> A255131(k), yields 24 -> 21 -> 18 -> 16 -> 15 -> 11 -> 8 -> 6 -> 3 before 0 is reached. Subtracting one from each gives [23, 20, 17, 15, 14, 10, 7, 5, 2], of which only 23, 17, 7, 5 and 2 are primes, thus a(4) = 5.
%o A278166 (Scheme) (definec (A278166 n) (if (= 1 n) (A277486 n) (+ (A277486 n) (A278166 (- n 1)))))
%Y A278166 Partial sums of A277486.
%Y A278166 Cf. A002828, A278167, A278168.
%K A278166 nonn
%O A278166 1,2
%A A278166 _Antti Karttunen_, Nov 13 2016