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A081310 Numbers having no representation as sum of a prime and an 3-smooth number. 4
1, 2, 36, 78, 96, 120, 126, 144, 156, 162, 186, 204, 210, 216, 222, 276, 288, 300, 306, 324, 328, 330, 336, 342, 366, 372, 378, 396, 408, 414, 426, 438, 456, 474, 486, 498, 516, 528, 534, 540, 546, 552, 562, 576, 582, 606, 612, 624, 630, 636, 666, 672, 690 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A081308(a(n))=0; complement of A081311.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

EXAMPLE

For all primes p<36 the greatest prime factor of 36-p is >3: 36-2=2*17, 36-3=3*11, 36-5=31, 36-7=29, 36-11=5*5, 36-13=23, 36-17=19, 36-19=17, 36-23=13, 36-29=7, 36-31=5, therefore 36 is a term.

PROG

(Haskell)

a081310 n = a081310_list !! (n-1)

a081310_list = filter ((== 0) . a081308) [1..]

-- Reinhard Zumkeller, Jul 04 2012

CROSSREFS

Cf. A000040, A003586.

Sequence in context: A037418 A239343 A058517 * A187298 A069067 A278930

Adjacent sequences:  A081307 A081308 A081309 * A081311 A081312 A081313

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Mar 17 2003

STATUS

approved

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Last modified June 16 05:18 EDT 2019. Contains 324145 sequences. (Running on oeis4.)