A342429 Starts of runs of 4 consecutive Niven numbers in base 3/2 (A342426).

1649373, 4029519, 15281054, 31906263, 43387386, 58198173, 94468958, 100084949, 131393766, 131986502, 140282279, 156786124, 211004079, 246960048, 253000850, 278206663, 310135917, 330168203, 351204398, 363280904, 412296883, 504736647, 515831624, 537255647, 566300238

Offset

1,1

Comments

Are there 5 consecutive Niven numbers in base 3/2? There are no such numbers below 3*10^9.

Links

Amiram Eldar, Table of n, a(n) for n = 1..100

Example

1649373 is a term since 1649373, 1649374, 1649375 and 1649376 are all Niven numbers in base 3/2.

Mathematica

s[0] = 0; s[n_] := s[n] = s[2*Floor[n/3]] + Mod[n, 3]; q[n_] := Divisible[n, s[n]]; v = q /@ Range[4]; seq = {}; Do[v = Join[Rest[v], {q[k]}]; If[And @@ v, AppendTo[seq, k - 3]], {k, 4, 10^7}]; seq

Crossrefs

Subsequence of A342426, A342427 and A342428.

Similar sequences: A141769 (decimal), A328207 (factorial), A328211 (Zeckendorf), A328215 (lazy Fibonacci), A330933 (binary), A334311 (base phi), A331824 (negabinary).

Sequence in context: A256953 A205985 A258953 * A144127 A072922 A204762

Adjacent sequences: A342426 A342427 A342428 * A342430 A342431 A342432

Keyword

nonn,base

Author

Amiram Eldar, Mar 11 2021

Status

approved