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A155953
Emirps of the form k^2 + k + 41.
0
71, 97, 113, 347, 743, 971, 1033, 1097, 1231, 1301, 1523, 1601, 1847, 1933, 3011, 3121, 3347, 3463, 7523, 9161, 9547, 9941, 10343, 12697, 13151, 15541, 15791, 17863, 30491, 31193, 32261, 32983, 39047, 70001, 72671, 74843, 75941, 77047, 79847
OFFSET
1,1
FORMULA
A005846 INTERSECTION A006567.
MAPLE
read("transforms") ; isA006567 := proc(n) local dr ; dr := digrev(n) ; RETURN(dr <> n and isprime(dr)) ; end: for n from 1 to 800 do p := n^2+n+41; if isprime(p) then if isA006567(p) then printf("%d, ", p) ; fi; fi; od: # R. J. Mathar, Feb 06 2009
CROSSREFS
KEYWORD
easy,nonn,base
AUTHOR
Jonathan Vos Post, Jan 31 2009
EXTENSIONS
Extended by R. J. Mathar and Dmitry Kamenetsky, Feb 06 2009
STATUS
approved