|
| |
|
|
A105090
|
|
Sum of the left diagonal in ordered 3 X 3 prime squares.
|
|
0
| |
|
|
36, 133, 253, 389, 533, 679, 841, 1007, 1175, 1327, 1489, 1703, 1859, 2021, 2209, 2405, 2571, 2769, 2977, 3139, 3319, 3545, 3733, 3905, 4135, 4361, 4525, 4721, 4891, 5099, 5319, 5549, 5743, 5987, 6177, 6361, 6599, 6813, 7021, 7193, 7425, 7675, 7927
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
FORMULA
| An ordered 3 X 3 prime square is 9 consecutive primes arranged in a square of the form p(9n-8) p(9n-7) p(9n-6) p(9n-5) p(9n-4) p(9n-3) p(9n-2) p(9n-1) p(9n) n=1, 2, .. Left diagonal is p(9n-8) p(9n-4) p(9n)
|
|
|
EXAMPLE
| The first 3 X 3 prime square
2 3 5
7 11 13
17 19 23
sum of left diagonal = 2 + 11 + 23 = 36 the first entry.
|
|
|
PROG
| (PARI) sum3x3left(n) = { local(x, j, s); forstep(x=0, n, 9, s=0; forstep(j=1, 9, 4, s += prime(x+j); ); print1(s", ") ) }
|
|
|
CROSSREFS
| Sequence in context: A007265 A155708 A196891 * A076578 A044368 A044749
Adjacent sequences: A105087 A105088 A105089 * A105091 A105092 A105093
|
|
|
KEYWORD
| easy,nonn
|
|
|
AUTHOR
| Cino Hilliard (hillcino368(AT)gmail.com), Apr 07 2005
|
| |
|
|
