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A147850
Parity of the digits sum of Sum_{j = 8*n-7..8*n} prime(j).
2
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, 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, 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
OFFSET
1,1
FORMULA
a(n) = 1 - A147781(n).
a(n) = A007953(17982*A127335(8*n-7)) mod 2. - R. J. Mathar, Jan 06 2009
EXAMPLE
2+3+5+7+11+13+17+19 = 1384614 (1+3+8+4+6+1+4) = 27 (1).
23+29+31+37+41+43+47+53 = 5466528 (5+4+6+6+5+2+8) = 36 (0).
461+463+467+479+487+491+499+503 = 69230700 (6+9+2+3+7) = 27 (1).
509+521+523+541+547+557+563+569 = 77862060 (7+7+8+6+2+6) = 36 (0).
MAPLE
A127335 := proc(n) add(ithprime(i), i=n..n+7) ; end:
A007953 := proc(n) add(i, i=convert(n, base, 10)) ; end:
A147850 := proc(n) A007953(17982*A127335(8*n-7)) mod 2 ; end:
for n from 1 to 200 do printf("%a, ", A147850(n)) ; od: # R. J. Mathar, Jan 06 2009
CROSSREFS
Cf. A147781.
Sequence in context: A361116 A100060 A328101 * A286046 A189215 A285128
KEYWORD
easy,nonn,base,less
AUTHOR
E.J.P. Vening, Nov 15 2008
EXTENSIONS
More terms from R. J. Mathar, Jan 06 2009
STATUS
approved