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 A234801 Start of a record-breaking run of consecutive arithmetic numbers. 0
 1, 5, 19, 41, 181, 347, 1497, 4955, 6026, 17101, 55923, 80897, 131729, 167585, 393033, 673859, 1484603, 2761381, 9220483, 13694929, 47390331, 82626389, 108980139, 717512595, 972975322, 1333553577, 2547417520, 3033935561, 21214519093, 24441006509, 261703848520 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS A number is called arithmetic (A003601) if the average of its divisors is integer. The run that starts at 261703848520 has length 132. LINKS EXAMPLE The first arithmetic numbers are 1, 3, 5, 6, 7, 11, hence the first two terms of the sequence are 1 and 5. MATHEMATICA arQ[n_] := 0 == Mod @@ (DivisorSigma[#, n] & /@ {1, 0}); r=c=n=0; While[True, If[arQ[++n], c++, If[c>r, r=c; Print@{c, n-c}]; c=0]] CROSSREFS Cf. A003601. Sequence in context: A033622 A091568 A147307 * A089148 A098319 A022267 Adjacent sequences:  A234798 A234799 A234800 * A234802 A234803 A234804 KEYWORD nonn AUTHOR Giovanni Resta, Jan 16 2014 STATUS approved

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Last modified June 17 19:10 EDT 2019. Contains 324198 sequences. (Running on oeis4.)