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a(n) = A002110(A280700(n)) = A046523(A283475(n)).
3

%I #11 Mar 19 2017 01:08:25

%S 1,2,6,2,30,2,6,30,210,2,6,30,30,210,30,30,2310,2,6,30,30,210,30,30,

%T 210,2310,30,30,210,210,30,210,30030,2,6,30,30,210,30,30,210,2310,30,

%U 30,210,210,30,210,2310,30030,30,30,210,210,30,210,2310,2310,30,210,210,2310,30030,210,510510,2,6,30,30,210,30,30

%N a(n) = A002110(A280700(n)) = A046523(A283475(n)).

%H Antti Karttunen, <a href="/A280705/b280705.txt">Table of n, a(n) for n = 0..8191</a>

%F a(n) = A002110(A280700(n)) = A046523(A283475(n)).

%t Table[Times @@ Prime@ Range@ DigitCount[2 n - DigitCount[2 n, 2, 1], 2, 1], {n, 0, 71}] (* or *)

%t Map[Times @@ MapIndexed[Prime[First[#2]]^#1 &, Reverse@ Sort[FactorInteger[#][[All, -1]]]] - Boole[# == 1] &, Map[Times @@ Prime@ Flatten@ Position[#, 1] &@ Reverse@ IntegerDigits[#, 2] &, Table[2 n - DigitCount[2 n, 2, 1], {n, 0, 71}]]] (* _Michael De Vlieger_, Mar 18 2017 *)

%o (Scheme)

%o (define (A280705 n) (A002110 (A280700 n)))

%o (define (A280705 n) (A046523 (A283475 n)))

%Y Cf. A002110, A005117, A046523, A280700, A283475.

%K nonn

%O 0,2

%A _Antti Karttunen_, Mar 16 2017