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A225714
Composite squarefree numbers n such that p(i)+4 divides n-4, where p(i) are the prime factors of n.
3
1054, 9541, 91039, 371074, 985054, 1043959, 1063003, 1107754, 1162498, 1357339, 1786054, 4018018, 5368549, 5820154, 8725747, 9994954, 12402709, 17138503, 17914054, 20855839, 23116009, 25077199, 26545054, 29247229, 30308359, 31424419, 33892759, 44141629
OFFSET
1,1
EXAMPLE
Prime factors of 1043959 are 7, 293 and 509. We have that (1043959-4)/(7+4) = 94905, (1043959-4)/(293+4) = 3515 and (1043959-4)/(509+4) = 2035.
MAPLE
with(numtheory); A225714:=proc(i, j) local c, d, n, ok, p, t;
for n from 2 to i do if not isprime(n) then p:=ifactors(n)[2]; ok:=1;
for d from 1 to nops(p) do if p[d][2]>1 or p[d][1]=j then ok:=0; break; fi;
if not type((n+j)/(p[d][1]-j), integer) then ok:=0; break; fi; od;
if ok=1 then print(n); fi; fi; od; end: A225714(10^9, -4);
CROSSREFS
KEYWORD
nonn
AUTHOR
Paolo P. Lava, May 13 2013
EXTENSIONS
a(20)-a(28) from Donovan Johnson, Nov 15 2013
STATUS
approved