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A239800
First appearance of n in A016014, or 0 if n never occurs.
2
1, 4, 12, 42, 19, 59, 92, 196, 184, 159, 334, 227, 317, 415, 256, 521, 514, 796, 734, 1861, 1691, 1997, 2053, 706, 5006, 5731, 3814, 2348, 5641, 1466, 19016, 5542, 26815, 8762, 18637, 5794, 31667, 5227, 17054, 35246, 51148, 5207, 59537, 75862, 54737, 117899, 58603, 81313, 30332, 100042, 205471, 113018, 102307, 21209, 63971, 321994, 62809, 648512
OFFSET
1,2
COMMENTS
Conjecture: a(n) > 0 for all n. - Jianing Song, Mar 09 2021
FORMULA
A016014(a(n)) = n.
MAPLE
isA239800 := proc(n, m) local k;
for k from 1 to n-1 while not isprime(2*m*k + 1) do od;
if k < n then false else isprime(2*m*n + 1) fi end:
A239800 := proc(n, SearchLimit) local k;
for k from 1 to SearchLimit do if isA239800(n, k) then return k fi od;
error "Search limit reached!" end:
A239800List := (ListLength, SearchLimit) ->
map(n -> A239800(n, SearchLimit), [$1..ListLength]):
A239800List(32, 65537); # Peter Luschny, Oct 05 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
Zak Seidov, Mar 27 2014
EXTENSIONS
Escape clause added by Jianing Song, Mar 09 2021
STATUS
approved