A068845 Final digits of the smallest prime starting with n!.
1, 3, 1, 1, 1, 7, 1, 29, 17, 43, 29, 13, 47, 19, 73, 37, 19, 41, 31, 41, 31, 1, 1, 37, 31, 37, 59, 41, 53, 41, 47, 1, 1, 89, 37, 53, 73, 1, 1, 43, 151, 1, 47, 1, 509, 127, 71, 167, 67, 167, 149, 67, 61, 139, 67, 59, 107, 241, 1, 61, 1, 149, 293, 127, 71, 151, 337, 107, 1
Offset: 1
Examples
a(7) = 11 because the smallest prime starting with 7! = 5040 is 504011 and so the last digits are 11.
References
- Amarnath Murthy, Smarandache Reciprocal function and an elementary inequality. Smarandache Notions Journal, Vol. 1-2-3, Spring 2000.
Crossrefs
Cf. A068844.
Programs
-
Maple
for i from 1 to 70 do a := nextprime(i!*10); b := 1; while(a-i!*10^b>=10^b) do b := b+1; a := nextprime(i!*10^b); end do; c[i] := a-i!*10^b; end do:q := seq(c[i],i=1..70);
-
Mathematica
Table[p = i!; k = 1; While[IntegerDigits[p] != Take[IntegerDigits[x = NextPrime[y = p*10^k]], IntegerLength[p]], k += 1]; x - y, {i, 69}] (* Jayanta Basu, Aug 09 2013 *)
Extensions
More terms from Sascha Kurz, Mar 17 2002
Comments