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A188917 Where powers of 2 occur in the union of squares and powers of 2. 4
1, 2, 3, 4, 6, 8, 11, 15, 20, 27, 37, 51, 70, 97, 135, 189, 264, 371, 521, 734, 1034, 1459, 2059, 2908, 4108, 5805, 8205, 11599, 16398, 23185, 32783, 46356, 65552, 92698, 131089, 185381, 262162, 370746, 524307, 741475, 1048596, 1482931, 2097173, 2965842, 4194326, 5931664, 8388631 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

A188915(a(n)) = A000079(n); A188915(A188916(n)) = A000290(n).

LINKS

Robert Israel, Table of n, a(n) for n = 0..6637

FORMULA

a(n) = floor((n+1)/2) + floor(2^(n/2)). - Robert Israel, Jun 13 2019

MAPLE

seq(floor((n+1)/2) + floor(2^(n/2)), n=0..100); # Robert Israel, Jun 13 2019

PROG

(Haskell)

a188917 n = a188917_list !! n

a188917_list = filter ((== 1) . a209229. a188915) [0..]

-- Reinhard Zumkeller, May 19 2015

CROSSREFS

Cf. A000079, A000290, A017910, A036987.

Cf. A188915, A188916, A209229, A006127 (subsequence).

Sequence in context: A237830 A023434 A087192 * A046935 A241334 A095814

Adjacent sequences:  A188914 A188915 A188916 * A188918 A188919 A188920

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Apr 14 2011

STATUS

approved

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Last modified September 27 09:09 EDT 2020. Contains 337380 sequences. (Running on oeis4.)