

A087636


Number of ndigit lunar primes.


7




OFFSET

1,2


COMMENTS

Although a(1) through a(6) are divisible by 9, a(7) is not.


LINKS

Table of n, a(n) for n=1..9.
D. Applegate, C program for lunar arithmetic and number theory
D. Applegate, M. LeBrun and N. J. A. Sloane, Dismal Arithmetic, arxiv:1107.1130 [math.NT], July 2011. [Note: we have now changed the name from "dismal arithmetic" to "lunar arithmetic"  the old name was too depressing]
D. Applegate, M. LeBrun, N. J. A. Sloane, Dismal Arithmetic, J. Int. Seq. 14 (2011) # 11.9.8.
Index entries for sequences related to dismal (or lunar) arithmetic


PROG

(PARI) A87636=[]; A087636(n)={while(#A87636<n, A87636=concat(A87636, 0)); !A87636[n] && A87636[n]=sum(k=10^(n1), 10^n1, is_A087097(k)); A87636[n]} \\ Store results in array A87636 to avoid recalculation.  M. F. Hasler, Nov 15 2018


CROSSREFS

Cf. A087062 (lunar product), A087097 (lunar primes), A087638 (partial sums).
Sequence in context: A214531 A271502 A235641 * A156218 A118293 A043430
Adjacent sequences: A087633 A087634 A087635 * A087637 A087638 A087639


KEYWORD

nonn,base,more


AUTHOR

Marc LeBrun and N. J. A. Sloane, Oct 26 2003


EXTENSIONS

a(6)a(9) from David Applegate, Nov 07 2003


STATUS

approved



