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A225710 Composite squarefree numbers n such that p(i)-10 divides n+10, where p(i) are the prime factors of n. 3
14, 22, 35, 55, 65, 77, 102, 110, 143, 165, 182, 221, 455, 494, 665, 935, 1001, 1173, 1430, 2717, 2795, 4505, 4526, 4862, 5957, 6479, 11526, 27521, 30485, 34661, 35126, 45917, 49715, 52910, 53846, 81686, 90574, 106865, 113477, 118745, 139073, 140822, 147095 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
Prime factors of 34661 are 11, 23 and 137. We have that (34661+10)/(11-10) = 34671, (34661+10)/(23-10) = 2667 and (34661+10)/(137-10) = 273.
MAPLE
with(numtheory); A225710:=proc(i, j) local c, d, n, ok, p, t;
for n from 1 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: A225710(10^9, 10);
MATHEMATICA
t = {}; n = 0; len = -2; While[len <= 262, n++; {p, e} = Transpose[FactorInteger[n]]; If[Length[p] > 1 && Union[e] == {1} && Union[Mod[n + 10, p - 10]] == {0}, AppendTo[t, n]; len = len + Length[IntegerDigits[n]] + 2]]; t (* T. D. Noe, May 17 2013 *)
CROSSREFS
Sequence in context: A187776 A048196 A305084 * A183185 A324526 A259750
KEYWORD
nonn
AUTHOR
Paolo P. Lava, May 13 2013
EXTENSIONS
Extended by T. D. Noe, May 17 2013
STATUS
approved

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Last modified July 7 17:32 EDT 2024. Contains 374112 sequences. (Running on oeis4.)