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Least start of a run of exactly n consecutive numbers that are norm-abundant in Gaussian integers (A332570).
0

%I #5 Feb 17 2020 07:49:44

%S 2,9,4,12,24,185,114,1649,692,4977,1412,416345,22624,72233,199892,

%T 25262152,1351880,130824185,16305324,1688906313,9412730,10393378914,

%U 721753400

%N Least start of a run of exactly n consecutive numbers that are norm-abundant in Gaussian integers (A332570).

%e a(2) = 9 since 9 and 10 are the least pair of 2 consecutive numbers that are norm-abundant in Gaussian integers, and 8 and 11 are not norm-abundant.

%t normAbQ[z_] := Abs[DivisorSigma[1, z, GaussianIntegers -> True]]^2 > 2*Abs[z]^2; n = 1; count = 0; max = 15; seq = Table[0, {max}]; While[count < max, n1 = n; If[normAbQ[n], While[normAbQ[++n1]]; d = n1 - n; If[d <= max && seq[[d]] == 0, count++; seq[[d]] = n]]; n = n1 + 1]; seq

%Y Cf. A005101, A096399, A096536, A103228, A103229, A103230, A332570.

%K nonn,more

%O 1,1

%A _Amiram Eldar_, Feb 16 2020