OFFSET
1,1
COMMENTS
An ordered 3 prime sided prime triangle is 6 consecutive primes arranged in an equilateral triangle of the form
...........p(6n-5)
.....p(6n-4).....p(6n-3)
.p(6n-2)...p(6n-1)......p(6n)
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
EXAMPLE
The first 3 prime sided prime triangle
2
3 5
7 11 13
adds up to 41, the first entry.
MATHEMATICA
Total/@Partition[Prime[Range[300]], 6] (* Harvey P. Dale, Apr 30 2022 *)
PROG
(PARI) sumtri3x3(n) = { local(x, j, s); forstep(x=1, n, 6, s = prime(x)+prime(x+1)+prime(x+2)+prime(x+3)+prime(x+4)+prime(x+5); print1(s", ") ) }
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Cino Hilliard, Apr 07 2005
STATUS
approved