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A146317
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Prime differences of primes subtracted from nearest cube
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3
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5, 3, 23, 17, 11, 5, 3, 89, 79, 67, 59, 53, 43, 37, 23, 19, 17, 5, 163, 139, 103, 79, 73, 13, 3, 2, 257, 239, 227, 191, 179, 173, 137, 113, 89, 71, 59, 53, 47, 29, 23, 17, 3, 367, 347, 281, 277, 269, 257, 241, 239, 229, 197, 179, 157, 149, 131, 127, 109, 107, 101, 71, 61
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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a(3)=23 because when the prime 23 is subtracted from the cube 64, the result is another prime, 41
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MAPLE
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R:= NULL: count:= 0: p:= 1:
while count < 100 do
p:= nextprime(p);
d:= ceil(p^(1/3))^3-p;
if isprime(d) then count:= count+1; R:= R, d fi;
od:
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PROG
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(UBASIC) 10 'cu less pr are prime 20 N=1:O=1 30 A=3:S=sqrt(N) 40 B=N\A 50 if B*A=N then 120 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 print R; N; Q:C=C+1:N=N+2:goto 30 100 if C=30 then stop 120 N=N+2:if N<R then 30:else O=O+1:goto 80
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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