OFFSET
1,2
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..1000
EXAMPLE
MATHEMATICA
q[k_] := q[k] = Module[{w = DigitCount[k, 2, 1], w2, m, n}, IntegerQ[m = k/w] && Divisible[m, w2 = DigitCount[m, 2, 1]] && Divisible[n = m/w2, DigitCount[n, 2, 1]]]; Select[Range[1.2*10^6], q[#] && q[#+1] &]
PROG
(PARI) s(n) = {my(w = hammingweight(n)); if(w == 1, 0, if(n % w, 1, 1 + s(n/w))); }
is1(k) = {my(sk = s(k)); sk == 0 || sk >= 4; }
lista(kmax) = {my(q1 = is1(1), q2); for(k = 2, kmax, q2 = is1(k); if(q1 && q2, print1(k-1, ", ")); q1 = q2); }
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Amiram Eldar, Oct 04 2024
STATUS
approved