

A087544


a(0) = 1, a(1) = 3, a(n) = smallest prime beginning with the sum of two previous terms.


4



1, 3, 41, 443, 48407, 488503, 5369101, 585760421, 59112952201, 5969871262259, 60289842144607, 6625971340686661, 66862611828312689, 7348858316899935071, 741572092872824776001, 7489209511897247110721, 82307816047700718867221
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OFFSET

0,2


LINKS

Robert Israel, Table of n, a(n) for n = 0..322


EXAMPLE

a(3) = 41, a(4) = 443, a(5) = 48407 is the smallest prime beginning with 41+443=484.


MAPLE

A[0]:= 1: A[1]:= 3:
for n from 2 to 20 do
s:= A[n2]+A[n1];
for d from 1 do
p:= nextprime(10^d*s);
if floor(p/10^d)=s then A[n]:= p; break fi
od
od:
seq(A[n], n=0..20); # Robert Israel, Dec 10 2018


MATHEMATICA

a[0] = 1; a[1] = 3; a[n_] := a[n] = Module[{s = a[n  1] + a[n  2]}, Do[p = 10^d*s; While[! PrimeQ[p], p = NextPrime[p]]; If[Floor[p/10^d] == s, Break[]], {d, 1, 20}]; p]; Array[a, 10, 0] (* Amiram Eldar, Dec 10 2018 from the Maple code *)


CROSSREFS

Cf. A087541, A087542, A087543.
Sequence in context: A181226 A159249 A328509 * A305667 A213378 A189356
Adjacent sequences: A087541 A087542 A087543 * A087545 A087546 A087547


KEYWORD

base,nonn


AUTHOR

Amarnath Murthy, Sep 13 2003


EXTENSIONS

More terms from Ray Chandler, Sep 23 2003


STATUS

approved



