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A307008
Numbers that are both prime-indexed primes and lucky-indexed lucky numbers.
2
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.
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
KEYWORD
nonn
AUTHOR
Amiram Eldar, Mar 19 2019
STATUS
approved