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A085745 2^n + n is a semiprime. 4
2, 11, 23, 34, 59, 69, 87, 95, 119, 123, 129, 171, 197, 239, 341, 425, 455, 471, 515, 519, 635, 765, 959, 1115, 1181, 1210 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..25.

FORMULA

a(n)=2k <=> A089535(n) is even <=> A089536(n)=2 <=> A089537(n)=4^k/2+k, and for any prime of this form, there is a term a(n)=2k in this sequence. - M. F. Hasler, Oct 08 2009

MATHEMATICA

Select[Range[1300], PrimeOmega[2^#+#]==2&] (* Harvey P. Dale, Dec 18 2014 *)

CROSSREFS

Cf. A089535, A089536, A089537.

Sequences A165767, A165768, A165769 are the analog for 2^n-n. - M. F. Hasler, Oct 08 2009

Sequence in context: A158189 A218255 A256481 * A106856 A045387 A103255

Adjacent sequences:  A085742 A085743 A085744 * A085746 A085747 A085748

KEYWORD

more,nonn

AUTHOR

Jason Earls, Jul 21 2003

EXTENSIONS

More terms from Ray Chandler, Nov 08 2003

341 from Donovan Johnson, Mar 06 2008

More terms from Sean A. Irvine, Oct 27 2009

STATUS

approved

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Last modified June 24 13:17 EDT 2019. Contains 324325 sequences. (Running on oeis4.)