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A257233
Multiplicity sequence for the alternating row sums of triangle A257232.
1
1, 7, 6, 6, 4, 2, 6, 2, 4, 6, 4, 2, 4, 2, 6, 2, 4, 6, 2, 4, 4, 2, 4, 2, 2, 4, 6, 6, 4, 2, 2, 2, 2, 2, 4, 4, 2, 6, 2, 2, 2, 6, 2, 4, 2, 4, 4, 2, 4, 2, 6, 2, 2, 2, 6, 6, 2, 2, 2, 2, 4, 2, 2, 2, 2, 4
OFFSET
1,2
COMMENTS
The sequence of alternating row sums of A257232 gives one times 1, seven times 2, 6 times 3, six times 4, four times 5, etc., in this order.
Is a(n) = A067970(n-2), n>=3 ? - R. J. Mathar, Apr 24 2015
FORMULA
The number m appears a(m) times in the sequence of row sums of triangle A257232 for m = 1, 2, ..., that is in sum(((-1)^(k-1))*(n - (k-1) - [isprime(k)]), k = 1..n) with [isprime(k)] = A010051(k) for n >= 1.
CROSSREFS
Cf. A257232.
Sequence in context: A031348 A247674 A109696 * A110948 A199871 A103616
KEYWORD
nonn,easy
AUTHOR
Wolfdieter Lang, Apr 19 2015
STATUS
approved