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A067372
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Integers expressible as the sum of (at least two) consecutive primes in at least 2 ways.
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14
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36, 41, 60, 72, 83, 90, 100, 112, 119, 120, 138, 143, 152, 180, 187, 197, 199, 204, 210, 221, 223, 228, 240, 251, 258, 276, 281, 287, 300, 304, 311, 323, 330, 340, 371, 372, 384, 390, 395, 401, 408, 410, 434, 439, 456, 462, 473, 480, 491, 492, 508, 510, 533
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OFFSET
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1,1
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LINKS
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FORMULA
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EXAMPLE
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36 = (17 + 19) = (5 + 7 + 11 + 13) or (#2,17) (#4,5).
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MATHEMATICA
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m=5!; lst={}; Do[p=Prime[a]; Do[p+=Prime[b]; If[p<Prime[m]*3+8, AppendTo[lst, p]], {b, a+1, m, 1}], {a, m}]; lst1=Sort[lst]; lst={}; Do[If[lst1[[n]]==lst1[[n+1]], AppendTo[lst, lst1[[n]]]], {n, Length[lst1]-1}]; Union[lst] (* Vladimir Joseph Stephan Orlovsky, Aug 15 2009 *)
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PROG
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(PARI) upto(n) = {my(s = 0, pr = List([0]), l = List(), res = List()); forprime(p = 2, n + 100, s+=p; listput(pr, s) ); for(i = 3, #pr, for(j = 2, i-1, if(pr[i] - pr[i-j] <= n, listput(l, pr[i] - pr[i-j]) , next(2) ) ) ); listsort(l); for(i = 2, #l, if(l[i-1] == l[i], listput(res, l[i]) ) ); Set(res); } \\ David A. Corneth, Aug 22 2019
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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