OFFSET
1,2
COMMENTS
The minimal appendage-sequence of primes with seed s and base b is defined as follows:
a(1) = s
a(2) = least prime that begins with s0;
a(3) = least prime that begins with a(2)0;
a(n) = least prime that begins with a(n-1)0.
LINKS
Clark Kimberling, Table of n, a(n) for n = 1..300
EXAMPLE
11 comes from a(3) = 10103 by appending 011 to a(3); the result is the least prime that begins with 10103. Triangular format:
1
101
10103
10103011
10103011013
1010301101309
10103011013090003
101030110130900030009
MATHEMATICA
base = 10; s = {{1}}; Do[NestWhile[# + 1 &, 1, (nn = #; ! PrimeQ[FromDigits[tmp=IntegerDigits[FromDigits[Flatten[IntegerDigits[Join[Last[s], {0}, IntegerDigits[nn - Sum[base^n, {n, l = NestWhile[# + 1 &, 1, ! (nn - (Sum[base^n, {n, #}]) < 0) &] - 1}], base, l + 1]]]]]], base]]) &]; AppendTo[s, {FromDigits[tmp]}], {20}];
Flatten[s] (* Peter J. C. Moses, Sep 03 2015 *)
CROSSREFS
KEYWORD
nonn,easy,base
AUTHOR
Clark Kimberling, Sep 25 2015
STATUS
approved