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A083266
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Sum of related numbers (counted in A073757) belonging to n: a(n) = A000203(n) + A023896(n) - 1; related = {divisor-set, RRS}.
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5
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1, 3, 6, 10, 15, 17, 28, 30, 39, 37, 66, 51, 91, 65, 83, 94, 153, 92, 190, 121, 157, 145, 276, 155, 280, 197, 282, 223, 435, 191, 496, 318, 377, 325, 467, 306, 703, 401, 523, 409, 861, 347, 946, 523, 617, 577, 1128, 507, 1085, 592, 887, 721, 1431, 605, 1171
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OFFSET
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1,2
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COMMENTS
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Sum of 1 <= m <= n such that gcd(m, n) is either 1 or m. - Michael De Vlieger, Apr 07 2021.
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LINKS
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EXAMPLE
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n=10: related terms = {1,2,5,10,3,7,9}, sum = 1+2+5+10+1+3+7+9-1 = 37 = a(10).
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MATHEMATICA
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Table[DivisorSigma[1, n] + Total@ Select[Range[2, n - 1], GCD[n, #] == 1 &], {n, 55}] (* or *)
{1}~Join~Array[DivisorSigma[1, #] + # EulerPhi[#]/2 - 1 &, 54, 2] (* Michael De Vlieger, Apr 07 2021 *)
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PROG
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CROSSREFS
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KEYWORD
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nonn,less
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AUTHOR
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STATUS
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approved
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