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%I #13 Jun 24 2023 19:17:11
%S 3,8,36,240,2520,32340,540540,10210200,232792560,6692786100,
%T 207030183360,7621298624940,311671001662020,13387011595197240,
%U 627972543920161440,33204048259778536140,1955349508631402683800,119211141709561183622340,7975609932439674026862360,565799151677779228023294480,41287621429375723111588738860
%N Row 2 of A276945: a(n) = A002110(n) + A002110(n+1).
%C a(n) = number whose primorial base representation (A049345) begins with digits "11", followed by n zeros: 11, 110, 1100, 11000, 110000, ...
%H Michael De Vlieger, <a href="/A276939/b276939.txt">Table of n, a(n) for n = 0..349</a>
%H <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>
%F a(n) = A002110(n) + A002110(n+1).
%t Total /@ Partition[FoldList[Times, 1, Prime@ Range[20]], 2, 1] (* _Michael De Vlieger_, Jun 24 2023 *)
%o (Scheme) (define (A276939 n) (+ (A002110 n) (A002110 (+ 1 n))))
%o (PARI) a(n) = factorback(primes(n)) + factorback(primes(n+1)); \\ _Michel Marcus_, Nov 23 2022
%Y Row 2 of A276945 (column 2 of A276943).
%Y Cf. A002110, A049345.
%K nonn,base
%O 0,1
%A _Antti Karttunen_, Sep 24 2016
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