A307008 Numbers that are both prime-indexed primes and lucky-indexed lucky numbers.

31, 367, 991, 1087, 1471, 3259, 3559, 5851, 6661, 6841, 8719, 9661, 10723, 11953, 13513, 18181, 20341, 21529, 22651, 23563, 25057, 31189, 39451, 70207, 72727, 75937, 81931, 85843, 87931, 92569, 93169, 108643, 131071, 136483, 143797, 149503, 150991, 163309

Offset

1,1

Comments

Intersection of A006450 and A032639.

Links

Table of n, a(n) for n=1..38.

Mathematica

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 *)

Crossrefs

Cf. A006450, A031157, A032639, A057698, A307009, A307010.

Sequence in context: A156150 A125419 A138440 * A161347 A107941 A142684

Adjacent sequences: A307005 A307006 A307007 * A307009 A307010 A307011

Keyword

nonn

Author

Amiram Eldar, Mar 19 2019

Status

approved