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 A258713 A001172(n)/2: Least k such that 2k is a sum of two odd primes in exactly n ways. 2
 0, 3, 5, 11, 17, 24, 30, 39, 42, 45, 57, 72, 60, 84, 90, 117, 123, 144, 120, 105, 162, 150, 180, 237, 165, 264, 288, 195, 231, 240, 210, 285, 255, 336, 396, 378, 438, 357, 399, 345, 519, 315, 504, 465, 390, 480, 435, 462, 450, 567, 717, 420, 495, 651 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Up to a(14) also indices of records in A002375, number of ways to write 2n as sum of two odd primes. - M. F. Hasler, Aug 21 2017 LINKS Robert Israel, Table of n, a(n) for n = 0..845 MAPLE g:= add(x^ithprime(i), i=2..1000): G:= series((g^2+add(x^(2*ithprime(i)), i=2..1000))/2, x, ithprime(1001)+3): A[0]:= 0: for k from 1 to (ithprime(1001)+1)/2 do   m:= coeff(G, x, 2*k);   if not assigned(A[m]) then A[m]:= k fi; od: for m from 1 while assigned(A[m]) do od: seq(A[i], i=0..m-1); # Robert Israel, Aug 21 2017 MATHEMATICA With[{s = Array[Count[Select[IntegerPartitions[2 #, 2], Length@ # == 2 &], p_ /; AllTrue[p, And[PrimeQ@ #, OddQ@ #] &]] &, 10^3]}, Table[FirstPosition[s, n][[1]] /. 1 -> 0, {n, 0, 53}]] (* Michael De Vlieger, Aug 21 2017 *) CROSSREFS Cf. A001172. Cf. A002375, A002372, A045917. Sequence in context: A099596 A200748 A063693 * A267517 A309427 A211435 Adjacent sequences:  A258710 A258711 A258712 * A258714 A258715 A258716 KEYWORD nonn AUTHOR N. J. A. Sloane, Jun 14 2015 EXTENSIONS Edited by M. F. Hasler, Aug 21 2017 Edited by Robert Israel, Aug 21 2017 STATUS approved

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Last modified August 25 13:50 EDT 2019. Contains 326324 sequences. (Running on oeis4.)