A349869 - OEIS

A349869

Nobly deficient numbers (A349759) that are not deficient numbers (A005100).

36, 48, 100, 112, 144, 162, 192, 196, 208, 324, 400, 448, 576, 784, 832, 900, 1296, 1458, 1600, 1764, 1936, 1984, 2304, 2368, 2500, 2704, 2752, 2916, 3072, 3136, 3600, 3904, 4288, 4356, 4624, 4672, 4900, 5184, 5776, 6084, 6208, 6400, 6976, 7056, 7168, 7744, 8100

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OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

EXAMPLE

36 is a term since it is not deficient, A000203(36) = 91 > 2*36 = 72, and both A000005(36) = 9 and A000203(36) = 91 are deficient.

MATHEMATICA

defQ[n_] := DivisorSigma[1, n] < 2*n; nobDefQ[n_] := And @@ defQ /@ DivisorSigma[{0, 1}, n]; Select[Range[10^4], !defQ[#] && nobDefQ[#] &]

CROSSREFS

Intersection of A023196 and A349759.

Cf. A000005, A000203, A005100, A349868.