This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A118717 Sum of two consecutive semiprimes. 6
 10, 15, 19, 24, 29, 36, 43, 47, 51, 59, 67, 69, 73, 77, 85, 95, 100, 106, 112, 115, 120, 127, 134, 143, 151, 159, 167, 171, 173, 178, 184, 187, 189, 201, 217, 226, 233, 237, 240, 243, 245, 252, 262, 267, 275, 283, 285, 288, 291, 301, 313, 317, 320, 327, 335 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Zak Seidov, Table of n, a(n) for n = 1..10000 FORMULA a(n) = A001358(n) + A001358(n+1). MATHEMATICA Total /@ Partition[Select[Range[50000], 2 == PrimeOmega[#] &], 2, 1] (* Zak Seidov, Jan 31 2017 *) PROG (PARI) isA001358(n)= { local(f, fct, sumpo); if(n <4, return(0) ); f=factor(n); fct=(matsize(f))[1]; sumpo= sum(i=1, fct, f[i, 2]); if ( sumpo != 2, return(0), return(1) ); } { oldn=0; for(n=4, 200, if( isA001358(n)==1, if( oldn !=0, print1(oldn+n, ", "); ); oldn=n; ); ); } \\ R. J. Mathar, May 23 2006 CROSSREFS Cf. A001358. Sequence in context: A139540 A285176 A135363 * A181529 A232501 A138593 Adjacent sequences:  A118714 A118715 A118716 * A118718 A118719 A118720 KEYWORD nonn AUTHOR Luc Stevens (lms022(AT)yahoo.com), May 21 2006 EXTENSIONS Corrected and extended by R. J. Mathar, May 23 2006 Edited by Ray Chandler, Oct 31 2010 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified March 21 22:19 EDT 2019. Contains 321382 sequences. (Running on oeis4.)