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%I #29 Jan 09 2021 02:09:27
%S 0,-1,-4,6,-8,9,0,-10,12,-14,15,0,-16,-18,20,21,22,-24,0,-25,26,-27,
%T -28,30,32,33,-34,0,-35,-36,-38,39,40,42,44,-45,0,-46,-48,49,-50,51,
%U -52,54,55,0,-56,-57,-58,60,62,-63,64,65,0,-66,-68,-69,70,-72,74,75,76,77,-78,0,-80,-81,-82,-84,85,86,87,-88
%N Erase the zeros of the sequence and the minus signs: what remains is A018252 (the nonprime numbers). Successive additions of the present terms placed between two zeros give the successive integers of A000040 (the prime numbers).
%C The successive zeros of the sequence could be replaced by the successive primes; the sequence would then start with 2, -1, -4, 6, -8, 9, 3, -10, 12, -14, 15, 5, -16, -18, 20, 21, 22, -24, 7, -25, 26, -27, -28, 30, 32, 33, -34, 11, -35, ...
%H Carole Dubois, <a href="/A338028/b338028.txt">Table of n, a(n) for n = 1..499</a>
%e 2 is the result of (-1) + (-4) + 6 + (-8) + 9,
%e 3 is the result of (-10) + 12 + (-14) + 15,
%e 5 is the result of (-16) + (-18) + 20 + 21 + 22 + (-24),
%e 7 is the result of (-25) + 26 + (-27) + (-28) + 30 + 32 + 33 + (-34),
%e 11 is the result of (-35) + (-36) + (-38) + 39 + 40 + 42 + 44 + (-45).
%e etc.
%Y Cf. A018252, A000040.
%K sign
%O 1,3
%A _Eric Angelini_ and _Carole Dubois_, Oct 08 2020