A089526 Numbers n such that 2*p(n)+3 and 2*p(n+1)+3 are consecutive primes, where p(i) denotes the i-th prime.
3, 7, 14, 33, 44, 45, 48, 49, 70, 75, 90, 174, 186, 213, 225, 246, 253, 254, 447, 505, 524, 531, 589, 592, 625, 665, 745, 766, 806, 866, 868, 989, 1047, 1084, 1091, 1105, 1131, 1191, 1202, 1228, 1257, 1280, 1333, 1395, 1410, 1429, 1495, 1512, 1550, 1643, 1651
Offset: 1
Keywords
Examples
p(3)=5, 2*5+3=13=p(6) p(4)=7, 2*7+3=17=p(7)
Links
- Harvey P. Dale, Table of n, a(n) for n = 1..1000
Programs
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Mathematica
cpQ[n_]:=Module[{p=2Prime[n]+3},PrimeQ[p]&&NextPrime[p]==2Prime[n+1]+3]; Select[Range[1700],cpQ] (* Harvey P. Dale, Nov 29 2014 *)