A373839 Numbers k such that k and A276150(k) are both multiples of 3, where A276150 is the digit sum in the primorial base.

0, 9, 18, 27, 33, 42, 51, 66, 75, 84, 90, 99, 108, 117, 123, 132, 141, 156, 165, 174, 180, 189, 198, 207, 213, 222, 231, 246, 255, 264, 270, 279, 288, 297, 303, 312, 321, 336, 345, 354, 360, 369, 378, 387, 393, 402, 411, 426, 435, 444, 450, 459, 468, 477, 483, 492, 501, 516, 525, 534, 540, 549, 558, 567, 573, 582

Offset

1,2

Comments

If x and y are terms and if A329041(x,y) = 1 (i.e., when adding x and y together will not generate any carries in the primorial base), then x+y is also a term. This follows from the quasi-exponential nature of A276086 and because A373837 is a multiplicative semigroup. See also A373599.

Links

Antti Karttunen, Table of n, a(n) for n = 1..12000

Index entries for sequences related to primorial base

Prog

(PARI) isA373839 = A373838;

Crossrefs

Intersection of A008585 and A373841.

Indices of multiples of 3 in A373833.

Cf. A276150, A329041, A373838 (characteristic function).

Cf. also A373599, A373837.

Sequence in context: A359225 A037337 A119310 * A037993 A044849 A282149

Adjacent sequences: A373836 A373837 A373838 * A373840 A373841 A373842

Keyword

nonn,base

Author

Antti Karttunen, Jun 19 2024

Status

approved