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A321023
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Numbers k such that sigma(k) = sigma(k + 15).
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1
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26, 62, 20840574, 25741470, 60765690, 102435795, 277471467, 361466454, 464465910, 1110512403, 1927430490, 2741174163, 3631266639, 3844534602, 3982743750, 4565968407, 4612184562, 4829319495, 4981969978, 7066794735, 13484870399, 14268004443, 14550390855, 15051147111
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OFFSET
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1,1
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LINKS
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EXAMPLE
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sigma(26) = sigma(41) = 42, sigma(62) = sigma(77) = 96.
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PROG
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(PARI) my(V=vector(15)); for(n=1, 2^28, my(s=sigma(n), r=(n%15)+1); if (s==V[r], print1(n-15, ", ")); V[r]=s)
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CROSSREFS
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Cf. A002961, A007373, A015861, A015863, A015865, A015866, A015867, A015876, A015877, A015880, A015881, A015882, A015883, A172335, A181647, A172333.
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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