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Smallest term A001043(k) with k>n such that A001043(k) is multiple of A001043(n).
1

%I #14 Mar 14 2017 00:29:20

%S 30,24,24,36,120,60,144,84,520,120,204,390,840,360,300,1120,240,384,

%T 276,288,456,648,2064,372,396,1428,630,648,2886,480,1290,3216,828,576,

%U 600,924,1920,990,1360,2112,3240,2604,1920,1560,1584,1230,2604,1350,2280,924

%N Smallest term A001043(k) with k>n such that A001043(k) is multiple of A001043(n).

%H Zak Seidov, <a href="/A283621/a283621.txt">Table of {n, m=A001043(n), k, a(n)=A001043(k), a(n)/m} for n = 1..200.</a>

%e a(1)=30 because A001043(1)=5 and A001043(6)=30=6*5,

%e a(2)=24 because A001043(2)=8 and A001043(5)=24=3*8,

%e a(5)=120 because A001043(1)=24 and A001043(17)=120=5*24.

%t With[{s = #},Table[k = n + 1; While[! Divisible[s[[k]], s[[n]]], k++]; s[[k]], {n, 50}]] &@ Map[Total, Partition[Prime@ Range[10^4 + 1], 2, 1]] (* _Michael De Vlieger_, Mar 13 2017, after _Harvey P. Dale_ at A001043 *)

%Y Cf. A001043 (sums of 2 successive primes).

%K nonn

%O 1,1

%A _Zak Seidov_, Mar 12 2017