A261022 - OEIS

%I #11 May 07 2019 15:35:46

%S 24,36,60,84,120,240,276,288,372,396,480,576,600,924,1064,1200,1236,

%T 1392,1620,1656,1764,1848,2088,2240,2280,2440,2460,2580,2640,2856,

%U 2964,3240,3264,3336,3444,3756,4044,4176,4224,4828,4860,5280,5376,5940,6300,6480,6660

%N Numbers that are the sum of 2 successive primes and also twice the sum of 2 lesser successive primes.

%C Terms in A001043 that are twice some lesser term. Numbers m such that both m and m/2 are terms in A001043.

%H Zak Seidov and Charles R Greathouse IV, <a href="/A261022/b261022.txt">Table of n, a(n) for n = 1..10000</a> (first 1000 terms from Seidov)

%e a(1)=24 because 24=A001043(5)=2*A001043(3), or 11+13=2*(5+7),

%e a(10)=396 because 396=A001043(45)=2*A001043(25), or 197+199=2*(97+101),

%e a(100)=16020 because 16020=A001043(1008)=2*A001043(552), or 8009+8011=2*(4003+4007),

%e a(1000)=324804 because 324804=A001043(14877)=2*A001043(7948), or 162391+162413=2*(81199+81203).

%t Module[{pr=Prime[Range[500]],p1,p2},p1=Total/@Partition[pr,2,1];p2=2p1;Intersection[p1,p2]] (* _Harvey P. Dale_, May 07 2019 *)

%o (PARI) p=3; forprime(q=5,1e4, t=p+q; if(t%4==0 && nextprime(t/4+1)+precprime(t/4) == t/2, print1(t", ")); p=q) \\ _Charles R Greathouse IV_, Aug 07 2015

%Y Cf. A001043.

%K nonn

%O 1,1

%A _Zak Seidov_, Aug 07 2015