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A090870
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a(n) is the smallest m such that d(m+k-1)=2k for k=1,...,n where d(t)= prime(t+1)-prime(t)(differences of consecutive primes in arithmetic progression).
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0
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OFFSET
| 1,1
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COMMENTS
| Is this sequence infinite?
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FORMULA
| a(n) = primePi(A016045(n)).
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EXAMPLE
| a(8)=6496152 because prime(6496152) = 113575727 and 113575727, 113575729, 113575733, 113575739, 113575747, 113575757, 113575769, 113575783, and 113575799 are nine consecutive primes with differences respectively 2, 4, 6, 8, 10, 12, 14, 16.
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MATHEMATICA
| a[n_] := (For[m=1, !Sum[(d[m+k-1]-2k)^2, {k, n}]==0, m++ ]; m); Do[Print[a[n]], {n, 8}]
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CROSSREFS
| Cf. A016045, A049232.
Sequence in context: A057736 A181263 A130309 * A088542 A075840 A096225
Adjacent sequences: A090867 A090868 A090869 * A090871 A090872 A090873
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KEYWORD
| more,nonn
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AUTHOR
| Farideh Firoozbakht (f.firoozbakht(AT)sci.ui.ac.ir), Dec 11 2003
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EXTENSIONS
| Extended and edited by T. D. Noe (noe(AT)sspectra.com), May 23 2011
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