|
%I #8 Mar 26 2019 19:44:11
%S 31,367,991,1087,1471,3259,3559,5851,6661,6841,8719,9661,10723,11953,
%T 13513,18181,20341,21529,22651,23563,25057,31189,39451,70207,72727,
%U 75937,81931,85843,87931,92569,93169,108643,131071,136483,143797,149503,150991,163309
%N Numbers that are both prime-indexed primes and lucky-indexed lucky numbers.
%C Intersection of A006450 and A032639.
%t m = 10^4; L = Table[2*i + 1, {i, 0, m}]; For[n = 2, n < Length[L], r = L[[n++]]; L = ReplacePart[L, Table[r*i -> Nothing, {i, 1, Length[L]/r}]]]; ll = L[[Select[L, # <= Length[L] &]]]; pp = Prime@ Prime@ Range@ PrimePi@ PrimePi@ (2m); Intersection[pp,ll] (* after Jean-François Alcover at A000959 and Giovanni Resta at A303403 *)
%Y Cf. A006450, A031157, A032639, A057698, A307009, A307010.
%K nonn
%O 1,1
%A _Amiram Eldar_, Mar 19 2019
|
