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A105089
Sum of the primes in ordered 3 X 3 prime squares.
1
100, 401, 763, 1163, 1601, 2053, 2501, 3017, 3517, 3997, 4479, 5105, 5571, 6045, 6639, 7217, 7741, 8331, 8927, 9417, 9949, 10613, 11201, 11711, 12467, 13063, 13559, 14159, 14653, 15311, 15937, 16661, 17253, 17959, 18531, 19093, 19813, 20461
OFFSET
1,1
COMMENTS
Partition the primes into consecutive and non-overlapping groups of nine primes and take the total of each group. - Harvey P. Dale, Sep 06 2018
LINKS
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, ...
EXAMPLE
The first 3 X 3 prime square
2 3 5
7 11 13
17 19 23
adds up to 100 the first entry in the table.
MATHEMATICA
With[{nn=40}, Total/@Partition[Prime[Range[9nn]], 9]] (* or *) Table[ Total[ Prime[Range[9i-8, 9i]]], {i, 40}] (* Harvey P. Dale, Sep 06 2018 *)
PROG
(PARI) sumsq3x3(n) = { local(x, j, s); forstep(x=0, n, 9, s=0; for(j=1, 9, s += prime(x+j); ); print1(s", ") ) }
CROSSREFS
Sequence in context: A250806 A250853 A017270 * A334707 A017510 A290654
KEYWORD
easy,nonn
AUTHOR
Cino Hilliard, Apr 07 2005
STATUS
approved