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 A146759 Number of primes p < 10^n such that c - p is prime, where c is the next cube greater than p. 3
 2, 7, 43, 224, 1355, 9306, 66200, 500249, 3883527, 31081813, 254358928 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE a(2) = 7 because at 10^2 there are 7 primes that, subtracted from the next higher value cube, produce prime differences: {3, 5, 41, 47, 53, 59, 61}. MATHEMATICA Table[Length[Select[Prime[Range[PrimePi[10^n]]], PrimeQ[Ceiling[#^(1/3)]^3 - #] &]], {n, 6}] (* T. D. Noe, Mar 31 2013 *) cpQ[n_]:=PrimeQ[Ceiling[Surd[n, 3]]^3-n]; nn=9; Module[{c=Table[If[ cpQ[n], 1, 0], {n, Prime[ Range[ PrimePi[ 10^nn]]]}]}, Table[ Total[ Take[c, PrimePi[10^p]]], {p, nn}]] (* Harvey P. Dale, Aug 13 2014 *) PROG (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 N1 print R; N; Q; C:N=N+2:C=C+1:goto 30 100 N=N+2:if N

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Last modified December 6 04:52 EST 2021. Contains 349562 sequences. (Running on oeis4.)