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A333427 Numbers k such that k and k+1 are both primorial base Niven numbers (A333426). 5
1, 8, 24, 32, 44, 64, 65, 132, 212, 224, 244, 245, 296, 368, 424, 425, 468, 560, 656, 720, 728, 737, 869, 1056, 1088, 1416, 1572, 1728, 2100, 2312, 2324, 2344, 2345, 2524, 2525, 2568, 2600, 2672, 2820, 2960, 3032, 3132, 3156, 3200, 3288, 3392, 3444, 4096, 4424 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

EXAMPLE

1 is a term since 1 and 2 are both primorial base Niven numbers.

MATHEMATICA

max = 6; bases = Prime @ Range[max, 1, -1]; nmax = Times @@ bases - 1; primNivenQ[n_] := Divisible[n, Plus @@ IntegerDigits[n, MixedRadix[bases]]]; q1 = primNivenQ[1]; seq = {}; Do[q2 = primNivenQ[n]; If[q1 && q2, AppendTo[seq, n - 1]]; q1 = q2, {n, 2, nmax}]; seq

CROSSREFS

Cf. A328205, A328209, A328213, A330927, A330931, A333426.

Sequence in context: A056196 A044069 A028628 * A128690 A283078 A319528

Adjacent sequences:  A333424 A333425 A333426 * A333428 A333429 A333430

KEYWORD

nonn

AUTHOR

Amiram Eldar, Mar 20 2020

STATUS

approved

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Last modified July 25 03:53 EDT 2021. Contains 346283 sequences. (Running on oeis4.)