A239800 First appearance of n in A016014, or 0 if n never occurs.

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

Links

Zak Seidov, Table of n, a(n) for n = 1..100

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

Cf. A016014, A239746, A239727.

Sequence in context: A242469 A242470 A242471 * A237501 A375547 A300124

Adjacent sequences: A239797 A239798 A239799 * A239801 A239802 A239803

Keyword

nonn

Author

Zak Seidov, Mar 27 2014

Extensions

Escape clause added by Jianing Song, Mar 09 2021

Status

approved