This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A117314 Twin-prime pairs expressible as the sum of two triangular numbers. 1
 11, 13, 29, 31, 137, 139, 191, 193, 461, 463, 659, 661, 821, 823, 1091, 1093, 1721, 1723, 2027, 2029, 2081, 2083, 2711, 2713, 3359, 3361, 3539, 3541, 3917, 3919, 6131, 6133, 6761, 6763, 7589, 7591, 7877, 7879, 7949, 7951, 8219, 8221, 9461, 9463, 9857 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE a(1) = 11 = 1 + 10; a(2) = 13 = 3 + 10. MATHEMATICA s = Select[Union@ Flatten@ Table[i(i + 1)/2 + j(j + 1)/2, {i, 200}, {j, 0, i}], PrimeQ@ # &]; t = Select[Range@Length@s - 1, s[[ # ]] + 2 == s[[ # + 1]] &]; Sort@Join[s[[t]], s[[t + 1]]] - Robert G. Wilson v, Apr 27 2006 CROSSREFS Cf. A117048, A117112. Sequence in context: A132245 A140567 A232880 * A115560 A045466 A158759 Adjacent sequences:  A117311 A117312 A117313 * A117315 A117316 A117317 KEYWORD easy,nonn AUTHOR Greg Huber, Apr 24 2006 EXTENSIONS More terms from Robert G. Wilson v, Apr 27 2006 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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.