A343047 - OEIS

%I #12 Apr 08 2021 00:34:17

%S 0,1,6,9,12,15,210,217,246,249,252,255,420,427,456,459,492,495,630,

%T 637,666,669,702,705,840,847,876,879,912,915,30030,30061,30246,30279,

%U 30252,30285,32550,32587,32586,32589,32592,32595,32760,32797,32796,32799,32832

%N a(n) = A343046(n, n).

%C This sequence has similarities with A087019 and A343043.

%H Rémy Sigrist, <a href="/A343047/b343047.txt">Table of n, a(n) for n = 0..10000</a>

%H Rémy Sigrist, <a href="/A343047/a343047.gp.txt">PARI program for A343047</a>

%H <a href="/index/Di#dismal">Index entries for sequences related to dismal (or lunar) arithmetic</a>

%H <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>

%F a(A002110(k)) = A002110(2*k) for any k >= 0.

%F a(A143293(k)) = A143293(2*k) for any k >= 0.

%e For n = 2:

%e - the primorial base representation of 2 is "10", so:

%e          1 0

%e        x 1 0

%e        -----

%e          0 0

%e      + 1 0

%e      -------

%e        1 0 0

%e - hence a(2) = 2*3 = 6.

%o (PARI) See Links section.

%Y Cf. A002110, A143293, A343046.

%Y Cf. A087019, A343043.

%K nonn,base

%O 0,3

%A _Rémy Sigrist_, Apr 05 2021