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%I #7 Mar 30 2012 17:23:05
%S 0,0,1,1,0,1,0,1,0,0,8,1,0,0,0,0,0,0,0,0,2,1,0,0,0,0,0,0,0,0,2,1,0,0,
%T 0,0,0,0,0,0,0,2,0,0,0,0,0,0,0,0,2,0,2,1,0,0,0,0,0,0,0,4,0,0,0,1,0,0,
%U 0,0,2,3,0,0,1,0,0,0,0,0,0,0,1,2
%N Number of ways n can be written as a multiple of its reversal A004086(n) +/- a prime p < n.
%C If n is not a multiple of 10, then a(n) < 20. The subsequence { a(10k) }, however, is unbounded. In particular, a(10^k)=2*A006880(k).
%e a(10)=8 because R(10)=01=1 and 10 = 3*1 + 7 = 5*1 + 5 = 7*1 + 3 = 8*1 + 2 = 12*1 - 2 = 13*1 - 3 = 15*1 - 5 = 17*1 - 7.
%o (PARI) a(n)={my(r=A004086(n)); sum(k=1, (2*n-1)\(r+!r), isprime(abs(n-k*r)))}
%Y Cf. A209063.
%K nonn,base
%O 0,11
%A _M. F. Hasler_, Mar 15 2012
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