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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

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

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

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Last modified August 23 00:46 EDT 2017. Contains 290953 sequences.