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A054001
Differences between numbers k such that k and k+1 have the same sum of divisors.
1
192, 751, 377, 30, 270, 1051, 289, 1390, 10477, 4032, 485, 787, 4812, 9041, 2568, 6252, 13746, 8101, 10253, 4908, 7, 4301, 8551, 16529, 2292, 5431, 5136, 16164, 9217, 13547, 1601, 4332, 7783, 16056, 3120, 7704, 28793, 44143, 14921, 58284
OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10134 (calculated using the b-file at A002961)
FORMULA
a(n) = A002961(n+1) - A002961(n).
MATHEMATICA
Differences[Select[Range[500000], DivisorSigma[1, #]== DivisorSigma[ 1, #+1]&]] (* Harvey P. Dale, Oct 16 2011 *)
Differences[SequencePosition[DivisorSigma[1, Range[350000]], {x_, x_}][[All, 1]]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jun 03 2021 *)
CROSSREFS
Sequence in context: A251083 A336944 A194647 * A051527 A305073 A101451
KEYWORD
nonn
AUTHOR
Asher Auel, Jan 12 2000
EXTENSIONS
More terms from David Wasserman, Mar 01 2002
STATUS
approved