1,1

It happens that under either 100^3 or 1000^2 the last prime subtrahend is 999983.

A(2)=61 because 61 is the 7th and last prime subtrahend under 10^3.

(Other) UBASIC: 10 'cu less pr are prime 20 N=1:O=1:C=1 30 A=3:S=sqrt(N):if N>10^3 then print N, C-1:stop 40 B=N\A 50 if B*A=N then 100 60 A=A+2 70 if A<=S then 40 80 R=O^3:Q=R-N 90 if N<R and N=prmdiv(N) and Q=prmdiv(Q) then if Q>1 print R; N; Q; C:N=N+2:C=C+1:goto 30 100 N=N+2:if N<R then 30:else O=O+1:goto 80

A146756 A146757 A146759

Sequence in context: A012167 A162167 A134282 this_sequence A083082 A009825 A065919

Adjacent sequences: A146757 A146758 A146759 this_sequence A146761 A146762 A146763

easy,more,nonn

Enoch Haga (Enokh(AT)comcast.net), Nov 02 2008