A333427 Numbers k such that k and k+1 are both primorial base Niven numbers (A333426).

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

Offset: 1

Author

Amiram Eldar, Mar 20 2020

Keywords

• nonn

Examples

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

Links

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

Crossrefs

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

Programs

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