A257233 - OEIS

A257233

Multiplicity sequence for the alternating row sums of triangle A257232.

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

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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

LINKS

Table of n, a(n) for n=1..66.

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

Adjacent sequences: A257230 A257231 A257232 * A257234 A257235 A257236

KEYWORD

nonn,easy

AUTHOR

Wolfdieter Lang, Apr 19 2015

STATUS

approved