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A176238
Natural numbers n such that d(d(n)+1) > 2
1
4, 9, 16, 24, 25, 30, 36, 40, 42, 49, 54, 56, 64, 66, 70, 78, 81, 88, 100, 102, 104, 105, 110, 114, 121, 128, 130, 135, 136, 138, 144, 152, 154, 165, 169, 170, 174, 182, 184, 186, 189, 190, 192, 195, 196, 222, 225, 230, 231, 232, 238, 240, 246, 248, 250, 255
OFFSET
1,1
COMMENTS
Complement to A166546.
LINKS
MATHEMATICA
Select[Range[300], DivisorSigma[0, DivisorSigma[0, #]+1]>2&] (* Harvey P. Dale, Jul 15 2021 *)
CROSSREFS
Sequence in context: A009853 A008030 A168086 * A139588 A320894 A122986
KEYWORD
nonn
AUTHOR
Giovanni Teofilatto, Apr 12 2010
EXTENSIONS
Extended by Giovanni Teofilatto, Apr 14 2010
Corrected (192 and 240 inserted) by R. J. Mathar, Apr 22 2010
STATUS
approved