A364727
Numbers k such that k and k+1 are both admirable numbers (A111592).
Original entry on oeis.org
29691198404, 478012798575, 2789405835075, 22929723392715
Offset: 1
A329187
Initial members of admirable triples: numbers k such that (k, k+2, k+4) are all admirable numbers (A111592).
Original entry on oeis.org
364, 17272, 54064, 383404, 1820812, 1945804, 2466604, 3283024, 3503164, 3820684, 3907984, 4407952, 5553712, 6095344, 6320524, 6820492, 7845232, 7966252, 8591212, 9841132, 10990864, 11841004, 12428272, 13695052, 13903372, 15032272, 15569932, 19007212, 19740304
Offset: 1
364 is in the sequence since 364, 366, and 368 are all admirable numbers.
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admQ[n_] := (ab = DivisorSigma[1, n] - 2 n) > 0 && EvenQ[ab] && ab/2 < n && Divisible[n, ab/2]; k = 0; s = {}; Do[If[admQ[n], k++; If[k > 2, AppendTo[s, n - 4]], k = 0], {n, 6, 2*10^6, 2}]; s (* for even terms; after Shyam Sunder Gupta at A231088 *)
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