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A109068 Products of two successive primes that can be partitioned in sum of three distinct primes which contain the prime divisors. 0
15, 35, 77, 221, 899, 1517, 2021, 5183, 8633, 11663, 23707, 27221, 36863, 41989, 47053, 57599, 60491, 77837, 111547, 164009, 233273, 324899, 372091, 416021, 471953, 522713, 568507, 608351, 665831, 680621 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Largest prime of sum of three primes are primes of the form p*q - p - q, where p and q are two successive primes (A096345).

LINKS

Table of n, a(n) for n=1..30.

FORMULA

a(n) = A096345(n) - A001043(n).

EXAMPLE

a(1) = 15 because 15 = 3+5+7 with 3*5 =15;

a(2) = 35 because 35 = 5+7+23 with 5*7=35;

a(3) = 77 because 77 = 7+11+59 with 7*11=77;

a(4) = 221 because 221= 13+17+191 with 13*17=221

PROG

(PARI) lista(nn) = {for (n=1, nn, p = prime(n); q = prime(n+1); prd = p*q; if (isprime(prd - p - q), print1(prd, ", ")); ); } \\ Michel Marcus, Jun 03 2013

CROSSREFS

Cf. A096345.

Sequence in context: A234542 A242235 A082663 * A334309 A238232 A061367

Adjacent sequences:  A109065 A109066 A109067 * A109069 A109070 A109071

KEYWORD

nonn

AUTHOR

Giovanni Teofilatto, Aug 17 2005

EXTENSIONS

More terms from Michel Marcus, Jun 03 2013

STATUS

approved

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Last modified August 14 19:09 EDT 2020. Contains 336483 sequences. (Running on oeis4.)