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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..105.

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: A004569 A100060 A328101 * A286046 A189215 A285128

Adjacent sequences:  A147847 A147848 A147849 * A147851 A147852 A147853

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

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Last modified October 21 22:47 EDT 2019. Contains 328315 sequences. (Running on oeis4.)