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A376793
Numbers k such that k and k+1 are both in A376616.
5
1, 1424, 2484, 4304, 4655, 6223, 10624, 13824, 20624, 22784, 29448, 33424, 33984, 36944, 41535, 43263, 45184, 45324, 65744, 66199, 68624, 69632, 70784, 74304, 74627, 99584, 103103, 103424, 105720, 114704, 120680, 139904, 147636, 164224, 166144, 192576, 199968
OFFSET
1,2
LINKS
EXAMPLE
1424 is a term since both 1424 and 1425 are in A376616: 1424/A000120(1424) = 356 and 356/A000120(356) = 89 are integers, and 1425/A000120(1425) = 285 and 285/A000120(285) = 57 are integers.
MATHEMATICA
q[k_] := q[k] = Module[{w = DigitCount[k, 2, 1]}, Divisible[k, w] && Divisible[k/w, DigitCount[k/w, 2, 1]]]; Select[Range[20000], q[#] && q[#+1] &]
PROG
(PARI) is1(k) = {my(w = hammingweight(k)); !(k % w) && !((k/w) % hammingweight(k/w)); }
lista(kmax) = {my(q1 = is1(1), q2); for(k = 2, kmax, q2 = is1(k); if(q1 && q2, print1(k-1, ", ")); q1 = q2); }
CROSSREFS
Subsequence of A330931 and A376616.
Subsequences: A376794, A376795.
Cf. A000120.
Sequence in context: A225567 A216444 A083428 * A183780 A068572 A236897
KEYWORD
nonn,base
AUTHOR
Amiram Eldar, Oct 04 2024
STATUS
approved