A349868 Nobly abundant numbers (A349758) that are not abundant numbers (A005101).
315, 495, 525, 585, 675, 693, 735, 765, 819, 825, 850, 855, 884, 950, 975, 988, 1012, 1035, 1071, 1078, 1125, 1150, 1196, 1197, 1210, 1215, 1274, 1275, 1276, 1287, 1292, 1305, 1323, 1364, 1395, 1425, 1449, 1450, 1508, 1550, 1564, 1612, 1617, 1628, 1665, 1666
Offset: 1
Keywords
Examples
315 is a term since it is not abundant, A000203(315) = 624 < 2*315 = 630, and both A000005(315) = 12 and A000203(315) = 624 are abundant numbers.
Links
- Amiram Eldar, Table of n, a(n) for n = 1..10000
Programs
-
Mathematica
abQ[n_] := DivisorSigma[1, n] > 2*n; nobAbQ[n_] := And @@ abQ /@ DivisorSigma[{0, 1}, n]; Select[Range[2000], !abQ[#] && nobAbQ[#] &]
Comments