OFFSET
1,2
LINKS
Eric Angelini, Another brick in the wall, Personal blog of the author, Feb. 2022.
EXAMPLE
a(1) = 1, a(2) = 2 and a(3) = 7 stacked form the prime number 127, which is what we want;
a(2) = 2, a(3) = 7 and a(4) = 21 stacked form the hereunder "brick":
.2
.7
21
From left to right we read (vertically) the two integers 2 and 271 which are prime and thus achieve a correct 3-integer brick;
a(3) = 7, a(4) = 21 and a(5) = 9 stacked form the hereunder "brick":
.7
21
.9
From left to right we read (vertically) the two integers 2 and 719 which are prime and thus achieve a correct 3-integer brick;
(...)
a(n) = 1739, a(n+1) = 997 and a(n+2) = 1771 stacked form the hereunder "brick":
1739
.997
1771
From left to right we read (vertically) the four integers 11, 797, 397 and 971 which are prime and thus achieve a correct 3-integer brick; etc.
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Carole Dubois and Eric Angelini, Feb 28 2022
STATUS
approved