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A236390 Positive integers m with 2^m*p(m) + 1 prime, where p(.) is the partition function (A000041). 3
1, 9, 11, 15, 34, 36, 43, 80, 152, 159, 168, 200, 205, 354, 402, 957, 1898, 2519, 2729, 2932, 3075, 3740, 4985, 5839, 7911, 9868, 10210, 24624, 27735, 31553, 37190 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
According to the conjecture in A236389, this sequence should have infinitely many terms.
The prime 2^(a(31))*p(a(31)) + 1 = 2^(37190)*p(37190) + 1 has 11405 decimal digits.
LINKS
EXAMPLE
a(1) = 1 since 2^1*p(1) + 1 = 2*1 + 1 = 3 is prime.
MATHEMATICA
q[n_]:=PrimeQ[2^n*PartitionsP[n]+1]
n=0; Do[If[q[m], n=n+1; Print[n, " ", m]], {m, 1, 10000}]
Select[Range[40000], PrimeQ[2^# PartitionsP[#]+1]&] (* Harvey P. Dale, Dec 30 2020 *)
CROSSREFS
Sequence in context: A063191 A329167 A216976 * A048464 A075824 A228951
KEYWORD
nonn
AUTHOR
Zhi-Wei Sun, Jan 24 2014
STATUS
approved

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Last modified April 25 03:15 EDT 2024. Contains 371964 sequences. (Running on oeis4.)