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A136288
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Primes which are the absolute value of the alternating sum and difference of the first n primes.
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1
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2, 3, 5, 7, 13, 19, 29, 53, 61, 71, 79, 83, 97, 103, 113, 139, 149, 151, 157, 163, 167, 191, 199, 233, 251, 281, 337, 347, 353, 397, 421, 433, 461, 563, 599, 643, 719, 773, 797, 811, 859, 883, 953, 977, 1031, 1039, 1061, 1063, 1091, 1097, 1153, 1187, 1201, 1213
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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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5 = abs(2-3+5-7+11-13) (first 6 primes),
7 = abs(2-3+5-7+11-13+17-19) (first 8 primes),
etc.
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MAPLE
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P:=proc(n) local i, s; s:=0; for i from 1 by 1 to n do s:=s+(-1)^i*ithprime(i); if isprime(abs(s)) then print(abs(s)); fi; od; end: P(1000);
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MATHEMATICA
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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