OFFSET
1,1
COMMENTS
To stay parallel with A090534, a(1) exists.
The greatest potential candidate, gpc(n), is of the form floor(10^n*97/99). The following is gpc(n)-a(n): 2, 0, 8, 78, 6, 80, 608, 6066, 0, 84, 808, 6680, 8, 6624, 662, 78, 606, 8618, 60008, 86, 600, 6000, 660, 608060, 808, ... .
LINKS
Robert G. Wilson v, Table of n, a(n) for n = 1..100
MATHEMATICA
fQ[p_] := Block[{id = IntegerDigits@ p}, Union@ PrimeQ[ FromDigits@# & /@ Partition[id, 2, 1]] == {True}]; f[n_] := Block[{p = NextPrime[10^n*97/99, -1]}, While[ !fQ@ p, p = NextPrime[p, -1]]; p]; f[1] = 7; Array[f, 19]
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Robert G. Wilson v, May 12 2014
STATUS
approved