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A242948
Numbers n such that A = n+DigitProd(n) is divisible by the largest power of 10 <= A.
2
1, 2, 3, 4, 5, 15, 35, 42, 44, 46, 48, 55, 91, 191, 272, 337, 692, 919, 1919, 2488, 5775, 7795, 7984, 17795, 17984, 28464, 29424, 394816, 489632, 683872, 3992224, 4996112, 7872992, 29927424, 89668224, 7991871488, 9968647168, 9991319797
OFFSET
1,2
COMMENTS
Trivially, numbers in A037124 satisfy this but are not included in this sequence.
It is not known if a(n) is infinite.
a(54) (if it exists) is > 10^49. - Hiroaki Yamanouchi, Jul 10 2014
LINKS
Hiroaki Yamanouchi, Table of n, a(n) for n = 1..53
EXAMPLE
272+2*7*2 = 300 is divisible by the highest power of 10 lower than 300 (in this case, 100). Thus 272 is a member of this sequence.
PROG
(PARI) DP(n)={p=1; d= digits(n); for(i=1, #d, p*=d[i]); return(p))}
for(n=1, 10^7, if(n%10!=0&&(n+DP(n))%10^(#Str(n+DP(n))-1)==0, print1(n, ", ")))
CROSSREFS
KEYWORD
nonn,base,hard
AUTHOR
Derek Orr, May 27 2014
EXTENSIONS
a(34)-a(38) from Hiroaki Yamanouchi, Jul 10 2014
STATUS
approved