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A133810 Numbers that are primally tight and have weakly ascending powers.

%I A133810 #11 Jun 30 2025 16:51:57
%S A133810 1,2,3,4,5,6,7,8,9,11,13,15,16,17,18,19,23,25,27,29,30,31,32,35,36,37,
%T A133810 41,43,47,49,53,54,59,61,64,67,71,73,75,77,79,81,83,89,97,101,103,105,
%U A133810 107,108,109,113,121,125,127,128,131,137,139,143,149,150,151,157,162
%N A133810 Numbers that are primally tight and have weakly ascending powers.
%C A133810 All numbers of the form p_1^k1*p_2^k2*...*p_n^k_n, where k1 <= k2 <= ... <= k_n and the p_i are n successive primes.
%H A133810 Reinhard Zumkeller, <a href="/A133810/b133810.txt">Table of n, a(n) for n = 1..10000</a>
%o A133810 (Haskell)
%o A133810 a133810 n = a133810_list !! (n-1)
%o A133810 a133810_list = 1 : filter f [2..] where
%o A133810    f x = (and $ zipWith (<=) eps $ tail eps) &&
%o A133810          (all (== 1) $ zipWith (-) (tail ips) ips)
%o A133810      where ips = map a049084 $ a027748_row x
%o A133810            eps = a124010_row x
%o A133810 -- _Reinhard Zumkeller_, Nov 07 2012
%Y A133810 Cf. A025487, A087980, A073491, A133808-A133813.
%Y A133810 Cf. A124010, A027748, A049084.
%K A133810 nonn
%O A133810 1,2
%A A133810 _Olivier Gérard_, Sep 23 2007