some "unknown" sequences

[franktaw at netscape.net]

>Can anyone solve these puzzles?

>%S A113904 1,7,1,8,9,5

My first thought was that this might be a date, but Wikipedia doesn't record any notable events on either Jan 7, 1895 or July 1, 1895 (nor Sep 5, 1718).  It might be a decimal number, but Plouffe's inverter suggests no obvious possibilities.  Maybe last digits of some sequence?

>%S A113785 2,3,13,175

Appears to be a(n)=a(n-1)^2 + 2*a(n-2).

>%S A112273 5,15,365,945
 
All divisible by 5, quotients are 1,3,73,189.  No help.

>%S A112027 7,8,4,6,25,26,13,15
 
Appears to be: add 1, divide by 2, add 2, take sum.  Presumably sum is over 4 preceding terms, so next four terms would be 79,80,40,42.  (Sum step can also be stated as multiply by 6 and subtract 11.)  Summing over all preceding terms would give an even number, and next divide by 2 would produce a non-integer.
 
If this is correct, sequence should be preceded by 1,2,1,3, which the originator presumably left off because it would make it "too easy".
 
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