A280705 - OEIS

A280705

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

1, 2, 6, 2, 30, 2, 6, 30, 210, 2, 6, 30, 30, 210, 30, 30, 2310, 2, 6, 30, 30, 210, 30, 30, 210, 2310, 30, 30, 210, 210, 30, 210, 30030, 2, 6, 30, 30, 210, 30, 30, 210, 2310, 30, 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

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OFFSET

0,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 0..8191

FORMULA

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

MATHEMATICA

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

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 *)

PROG

(Scheme)

(define (A280705 n) (A002110 (A280700 n)))

(define (A280705 n) (A046523 (A283475 n)))

CROSSREFS

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

Sequence in context: A076743 A131980 A217448 * A027760 A141056 A141498

Adjacent sequences: A280702 A280703 A280704 * A280706 A280707 A280708

KEYWORD

nonn

AUTHOR

Antti Karttunen, Mar 16 2017

STATUS

approved