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A249334
Numbers n for which the digital sum contains the same distinct digits as the digital product.
7
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 22, 99, 123, 132, 213, 231, 312, 321, 1124, 1137, 1142, 1173, 1214, 1241, 1317, 1371, 1412, 1421, 1713, 1731, 2114, 2141, 2411, 3117, 3171, 3344, 3434, 3443, 3711, 4112, 4121, 4211, 4334, 4343, 4433, 7113, 7131, 7311, 11125, 11133
OFFSET
1,3
COMMENTS
Numbers n such that A007953(n) contains the same distinct digits as A007954(n). (But either of the two may contain some digit(s) more than once.)
Supersequence of A034710 (positive numbers for which the sum of digits is equal to the product of digits).
Union of A034710 and A249335.
The sequence is infinite since, e.g., A002275(n) = (10^n-1)/9 is in the sequence for all n = A002275(k), k>=0; and more generally N(k,d) = A002275(n)-1+d with n = (A002275(k)-1)*d+1, k>0 and 0<d<10 (with n digits which sum to n-1+d = (10^k-1)/9*d). - M. F. Hasler, Oct 29 2014
LINKS
Chai Wah Wu, Table of n, a(n) for n = 1..10000 (n = 1..201 from Jaroslav Krizek).
EXAMPLE
1137 is a member since 1+1+3+7 = 12 and 1*1*3*7 = 21.
3344 is in this list because 3+3+4+4=14 has the same (distinct) digits as 3*3*4*4=144.
PROG
(Magma) [n: n in [1..10^6] | Set(Intseq(&*Intseq(n))) eq Set(Intseq(&+Intseq(n)))]
(PARI) is_A249334(n)=Set(digits(sumdigits(n)))==Set(digits(prod(i=1, #n=digits(n), n[i]))) \\ M. F. Hasler, Oct 29 2014
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Jaroslav Krizek, Oct 25 2014
STATUS
approved