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%I #10 Nov 14 2016 10:38:12
%S 1,1,2,2,2,3,5,6,7,7,9,10,12,12,15,17,17,20,20,22,22,23,27,29,32,34,
%T 38,40,40,43,46,48,53,56,60,63,66,69,71,75,77,79,83,86,89,92,98,101,
%U 102,105,109,111,117,120,123,125,130,135,140,145,149,152,159,163,167,173,177,179,183,189,194,199,204,208,215,219,223,230,234
%N a(n) = number of primes encountered before reaching 0 when starting from k = ((n+1)^2)-1 and iterating map k -> k - A002828(k).
%C a(n) = number of terms of A277888 less than (n+1)^2.
%H Antti Karttunen, <a href="/A278167/b278167.txt">Table of n, a(n) for n = 1..10000</a>
%F a(1) = A277487(1); for n > 1, a(n) = A277487(n) + a(n-1).
%e 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. Of these numbers only 11 and 3 are primes, thus a(4) = 2.
%o (Scheme) (definec (A278167 n) (if (= 1 n) (A277487 n) (+ (A277487 n) (A278167 (- n 1)))))
%Y Partial sums of A277487.
%Y Cf. A002828, A255131, A278166, A278168, A277888.
%K nonn
%O 1,3
%A _Antti Karttunen_, Nov 13 2016
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