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A067827
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Even numbers k such that k/2 is nonprime and sigma(k+1) > sigma(k).
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1
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2, 404, 494, 524, 692, 764, 854, 944, 1034, 1124, 1394, 1682, 1784, 1826, 1844, 2114, 2204, 2294, 2414, 2534, 2564, 2714, 2774, 2804, 2834, 2924, 3002, 3014, 3044, 3074, 3266, 3284, 3374, 3434, 3464, 3644, 3674, 3794, 3842, 3854, 3884, 3914, 3926, 4094
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internal format)
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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Select[Range[2, 4000, 2], !PrimeQ[#/2] && DivisorSigma[1, # + 1] > DivisorSigma[1, #] &] (* Amiram Eldar, Apr 29 2022 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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