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A145470
A positive integer k is included if d(k) = d(k+1) + d(k+2), where d(k) is the number of divisors of k.
3
12, 30, 42, 45, 56, 66, 112, 220, 261, 282, 294, 297, 308, 342, 364, 390, 416, 477, 492, 513, 516, 532, 536, 555, 567, 572, 580, 620, 621, 632, 651, 700, 705, 768, 777, 786, 795, 812, 832, 836, 860, 880, 884, 891, 897, 906, 957, 975, 976, 981, 992, 1000, 1005
OFFSET
1,1
LINKS
MATHEMATICA
Transpose[Select[Partition[Range[1010], 3, 1], DivisorSigma[0, First[#]] == DivisorSigma[0, Last[#]] + DivisorSigma[0, #[[2]]]&]][[1]] (* Amiram Eldar, Jul 17 2019 after Harvey P. Dale at A175116 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Leroy Quet, Oct 11 2008
EXTENSIONS
Extended by Ray Chandler, Oct 27 2008
STATUS
approved