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A151995
a(1)=1; thereafter a(n) is smallest positive number not already in the sequence such that the sum a(1)+...+a(n) divides the concatenation a(1)...a(n).
4
1, 2, 6, 250488, 19986, 118030, 133970, 693810, 2231328, 3407286, 5733260, 25176334, 75529002, 1913932644, 2692452, 5413116264, 6766395330, 2492882490, 9544178676, 19819882608, 10086515692, 10541120510, 4147755864, 6025730266
OFFSET
1,2
EXAMPLE
1+2 (=3) divides 12 --> HIT
1+2+3 (=6) does not divide 123
1+2+4 (=7) does not divide 124
1+2+5 (=8) does not divide 125
1+2+6 (=9) divides 126 --> HIT
...
126250488 == (1+2+6+250488) * 504
...
The sum of the first 14 terms, 2027226147, divides their concatenation
1262504881998611803013397069381022313283407286573326025176334755290021913932644,
giving a quotient of
622774565071062988323520804204101612390759720490782533881916606559052.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Oct 07 2009, based on a posting to the Sequence Fans Mailing List by Eric Angelini, Sep 29 2009
EXTENSIONS
More terms from Jack Brennen, John W. Layman, Charles R Greathouse IV and Robert G. Wilson v, Sep 30 2009. Jack Brennen found a(14).
Definition corrected by Zak Seidov, Oct 08 2009
a(15)-a(24) from Donovan Johnson, Jul 20 2010
STATUS
approved