A128817 - OEIS

This site is supported by donations to The OEIS Foundation.

A128817

Primes which are 4 greater than the product of lesser twin primes.

7, 19, 81349, 3335149, 196773559, 13970922409, 150983758430839 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,1`
	COMMENTS	`Also primes which are 4 greater than A097489 terms where A097489 = product of first n terms of A001359 and A001359 = Lesser of twin primes.`
	FORMULA	`Define twinl#(n)as the product of the first n lesser twin primes. Then if twinl#+4 is prime, list it.`
	EXAMPLE	`twinl#(2) = 3*5=15. 15+4 = 19 prime and the second term in the table.`
	PROG	`(PARI) twiprimesl(n, a) = { local(pr, x, y, j); for(j=1, n, pr=1; for(x=1, j, pr*=twinl(x); ); y=pr+a; if(ispseudoprime(y), print1(y", ") ) ) } twinl(n) = \The n-th lower twin prime { local(c, x); c=0; x=1; while(c<n, if(isprime(prime(x)+2), c++); x++; ); return(prime(x-1)) }`
	CROSSREFS	`Sequence in context: A201479 A191624 A057866 * A037005 A022419 A070413` `Adjacent sequences: A128814 A128815 A128816 * A128818 A128819 A128820`
	KEYWORD	`nonn`
	AUTHOR	`Cino Hilliard (hillcino368(AT)hotmail.com), May 08 2007`

Content is available under The OEIS End-User License Agreement .

Last modified February 15 21:56 EST 2012. Contains 205860 sequences.