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A147850 Parity of the digits sum of Sum_{j = 8*n-7..8*n} prime(j). 2

%I

%S 1,0,1,0,1,0,0,1,1,0,0,1,0,1,0,1,1,1,1,1,1,0,1,1,0,1,1,0,0,0,0,1,0,1,

%T 1,1,0,0,0,0,1,0,1,0,0,0,0,1,1,1,0,0,0,0,0,0,0,0,0,0,1,1,0,0,0,0,1,0,

%U 1,1,0,0,1,1,0,0,1,1,1,1,1,0,0,0,0,0,0,0,0,1,1,1,1,0,1,0,1,0,1,0,0,0,0,0,0

%N Parity of the digits sum of Sum_{j = 8*n-7..8*n} prime(j).

%F a(n) = 1 - A147781(n).

%F a(n) = A007953(17982*A127335(8*n-7)) mod 2. - _R. J. Mathar_, Jan 06 2009

%e 2+3+5+7+11+13+17+19 = 1384614 (1+3+8+4+6+1+4) = 27 (1).

%e 23+29+31+37+41+43+47+53 = 5466528 (5+4+6+6+5+2+8) = 36 (0).

%e 461+463+467+479+487+491+499+503 = 69230700 (6+9+2+3+7) = 27 (1).

%e 509+521+523+541+547+557+563+569 = 77862060 (7+7+8+6+2+6) = 36 (0).

%p A127335 := proc(n) add(ithprime(i),i=n..n+7) ; end:

%p A007953 := proc(n) add(i,i=convert(n,base,10)) ; end:

%p A147850 := proc(n) A007953(17982*A127335(8*n-7)) mod 2 ; end:

%p for n from 1 to 200 do printf("%a,",A147850(n)) ; od: # _R. J. Mathar_, Jan 06 2009

%Y Cf. A147781.

%K easy,nonn,base,less

%O 1,1

%A _E.J.P. Vening_, Nov 15 2008

%E More terms from _R. J. Mathar_, Jan 06 2009

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Last modified November 19 11:09 EST 2019. Contains 329319 sequences. (Running on oeis4.)