OFFSET
1,1
EXAMPLE
30 is in the sequence since 30 = 6 + 24; neither d(6) = 4 nor d(24) = 8 divide 30, but d(6*24) = d(144) = 15 | 30 and d(24-6) = d(18) = 6 | 30.
MATHEMATICA
Flatten[Table[If[Sum[(1 - Ceiling[n/DivisorSigma[0, i (n - i)]] + Floor[n/DivisorSigma[0, i (n - i)]]) (1 - Ceiling[n/DivisorSigma[0, n - 2 i]] + Floor[n/DivisorSigma[0, n - 2 i]]) (Ceiling[n/DivisorSigma[0, i]] - Floor[n/DivisorSigma[0, i]]) (Ceiling[n/DivisorSigma[0, n - i]] - Floor[n/DivisorSigma[0, n - i]]), {i, Floor[(n - 1)/2]}] > 0, n, {}], {n, 1000}]]
CROSSREFS
KEYWORD
nonn
AUTHOR
Wesley Ivan Hurt, Jul 21 2019
EXTENSIONS
Name corrected by Wesley Ivan Hurt, Jul 24 2019
STATUS
approved