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A105092 Sum of the sides of ordered 2 prime sided prime triangles. 0
20, 62, 118, 194, 262, 346, 422, 502, 602, 658, 790, 878, 974, 1066, 1162, 1266, 1378, 1462, 1578, 1658, 1766, 1882, 2030, 2122, 2238, 2338, 2458, 2570, 2662, 2762, 2866, 2986, 3106, 3290, 3406, 3514, 3614, 3698, 3830, 3918, 4022, 4150, 4310, 4430, 4538 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..45.

FORMULA

An ordered 2 prime sided prime triangle is 3 consecutive primes arranged in a triangle of the form p(3n-2) p(3n-1) p(3n ) n=1, 2, .. and sides s1 = p(3n-2) p(3n-1) s2 = p(3n-1) p(3n ) s3 = p(3n-2) p(3n )

EXAMPLE

The first 2 prime sided prime triangle is

2

3 5

sum of sides = (2+3) + (3+5) + (2+5) = 20 the first entry.

PROG

(PARI) sumsidestri3x3(n) = { local(x, j, s); forstep(x=1, n, 3, s = prime(x)+prime(x+1)+prime(x+2); print1(2*s", ") ) }

CROSSREFS

Sequence in context: A041782 A041784 A276962 * A112144 A007248 A117431

Adjacent sequences:  A105089 A105090 A105091 * A105093 A105094 A105095

KEYWORD

easy,nonn

AUTHOR

Cino Hilliard, Apr 07 2005

STATUS

approved

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Last modified June 23 13:26 EDT 2017. Contains 288665 sequences.