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A363792
Starts of runs of 4 consecutive integers that are primitive binary Niven numbers (A363787).
3
8255214, 14673870, 29092590, 33185646, 41743854, 47697390, 48069486, 56348622, 56999790, 58116078, 59604462, 60534702, 60813774, 61837038, 62581230, 64069614, 64999854, 65371950, 66581262, 66674286, 75232494, 83418606, 86767470, 88069806, 92255886, 95418702, 96441966, 99511758, 99604782
OFFSET
1,1
COMMENTS
There are no runs of 5 or more consecutive integers that are primitive binary Niven numbers (see the second comment in A330933).
LINKS
EXAMPLE
8255214 is a term since 8255214, 8255215, 8255216 and 8255217 are all primitive binary Niven numbers.
MATHEMATICA
binNivQ[n_] := Divisible[n, DigitCount[n, 2, 1]]; primBinNivQ[n_] := binNivQ[n] && ! (EvenQ[n] && binNivQ[n/2]);
seq[kmax_] := Module[{quad = primBinNivQ /@ Range[4], s = {}, k = 5}, While[k < kmax, If[And @@ quad, AppendTo[s, k - 4]]; quad = Join[Rest[quad], {primBinNivQ[k]}]; k++]; s]; seq[3*10^7]
PROG
(PARI) isbinniv(n) = !(n % hammingweight(n));
isprim(n) = isbinniv(n) && !(!(n%2) && isbinniv(n/2));
lista(kmax) = {my(quad = vector(4, i, isprim(i)), k = 5); while(k < kmax, if(vecsum(quad) == 4, print1(k-4, ", ")); quad = concat(vecextract(quad, "^1"), isprim(k)); k++); }
CROSSREFS
Sequence in context: A116337 A234049 A233484 * A234383 A192630 A379179
KEYWORD
nonn,base
AUTHOR
Amiram Eldar, Jun 22 2023
STATUS
approved