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A073535
Numbers k such that S(k+2) = d(k)+2, where S(k) is the Kempner function (A002034) and d(k) is the number of divisors of k (A000005).
4
1, 2, 14, 34, 46, 96, 142, 178, 196, 240, 358, 598, 718, 1048, 1350, 1398, 1598, 1790, 1798, 2310, 2350, 2398, 2698, 3040, 3232, 3598, 3820, 3838, 5094, 5290, 5388, 6298, 6368, 6398, 6420, 6910, 7198, 7348, 7434, 8622, 8958, 9448, 11198, 11518, 14012, 14398
OFFSET
1,2
LINKS
MATHEMATICA
kemp[n_] := Module[{m = 1}, While[!IntegerQ[m!/n], m++]; m]; aQ[n_] := kemp[n + 2] == DivisorSigma[0, n] + 2; Select[Range[1000], aQ] (* Amiram Eldar, Jan 20 2019 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Jason Earls, Aug 27 2002
EXTENSIONS
a(21)-a(46) from Amiram Eldar, Jan 20 2019
STATUS
approved