

A077345


a(n) is the nth prime whose decimal expansion begins with the decimal expansion of n.


4



11, 23, 37, 401, 509, 617, 719, 829, 953, 1033, 1171, 1279, 1373, 1483, 15013, 1697, 17021, 18049, 19001, 20051, 21067, 22031, 23027, 24097, 25127, 26107, 27103, 28123, 29153, 30161, 31159, 32189, 33161, 34259, 35171, 36241, 37243, 38299, 39241, 40237, 41263
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OFFSET

1,1


COMMENTS

Original name was: Final terms of rows in A077344.
Subsidiary sequence: There can be a rearrangement of primes in groups so that the nth group contains n primes beginning with n and not occurring earlier. E.g. the initial term of row 11 would be 113 and not 11.


LINKS



MAPLE

u:= (h, t)> select(isprime, [seq(h*10^t+k, k=0..10^t1)]):
A:= proc(n, k) local l, p;
l:= proc() [] end; p:= proc() 1 end;
while nops(l(k))<n do p(k):= p(k)+1;
l(k):= [l(k)[], u(k, p(k))[]]
od: l(k)[n]
end:
a:= n> A(n$2):


MATHEMATICA

u[h_, t_] := Select[Table[h*10^t + k, {k, 0, 10^t  1}], PrimeQ];
A[n_, k_] := Module[{l, p}, l[_] = {}; p[_] = 1; While[Length[l[k]] < n, p[k] = p[k] + 1; l[k] = Join[l[k], u[k, p[k]]]]; l[k][[n]]];
a[n_] := A[n, n];


CROSSREFS



KEYWORD

base,easy,nonn


AUTHOR



EXTENSIONS



STATUS

approved



