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A249125
Composite numbers which are a multiple of the concatenation of their prime factors A084317.
2
4, 8, 9, 16, 25, 27, 32, 49, 50, 64, 81, 100, 121, 125, 128, 169, 200, 243, 250, 256, 289, 343, 361, 400, 500, 512, 529, 625, 729, 800, 841, 961, 1000, 1024, 1250, 1331, 1369, 1600, 1681, 1849, 2000, 2048, 2187, 2197, 2209, 2401, 2500, 2809, 3125, 3200, 3481, 3721, 4000, 4096, 4489, 4913, 5000, 5041, 5329, 6241, 6250, 6400
OFFSET
1,1
COMMENTS
Prime numbers are excluded since they trivially satisfy the condition.
Multiplicity of the prime factors is ignored.
Among the first 10000 terms, the 182 which are not prime powers are of the form 2^h * 5^k. - Giovanni Resta, May 29 2017
LINKS
MATHEMATICA
Select[Range[6400], CompositeQ[#] && Mod[#, FromDigits@ Flatten[ IntegerDigits /@ First /@ FactorInteger@#]] == 0 &] (* Giovanni Resta, May 29 2017 *)
PROG
(PARI) for(n=2, 9999, isprime(n)||n%A084317(n)||print1(n", "))
CROSSREFS
KEYWORD
nonn,base
AUTHOR
M. F. Hasler, Oct 21 2014
STATUS
approved