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A145108 Multiples of 4 that are primally tight and have strictly ascending powers. 2
4, 8, 16, 32, 64, 108, 128, 256, 324, 512, 648, 972, 1024, 1944, 2048, 2916, 3888, 4096, 5832, 8192, 8748, 11664, 16384, 17496, 23328, 26244, 32768, 34992, 52488, 65536, 67500, 69984, 78732, 104976, 131072, 139968, 157464, 209952, 236196, 262144 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

All numbers of the form 2^k0*p_1^k1*p_2^k2*...*p_n^k_n, where 2 <= k0 < k1 < k2 < ... < k_n and the p_i are n successive primes.

Subset of A073491, A133808, A133809, A133810 and A133811.

LINKS

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

PROG

(Haskell)

a145108 n = a145108_list !! (n-1)

a145108_list = filter ((== 0) . (`mod` 4)) a133809_list

-- Reinhard Zumkeller, Apr 14 2015

CROSSREFS

Cf. A025487, A087980, A073491, A133808, A133809, A133810, A133811, A133812, A133813.

Cf. A008586.

Sequence in context: A121986 A285906 A172042 * A108569 A196875 A111073

Adjacent sequences:  A145105 A145106 A145107 * A145109 A145110 A145111

KEYWORD

nonn

AUTHOR

Reikku Kulon, Oct 02 2008

STATUS

approved

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Last modified November 24 00:27 EST 2017. Contains 295164 sequences.