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 A173817 The half of sum of the numbers in the n-th row of Gilbreath's triangle (A036262). 0
 1, 2, 4, 5, 10, 10, 13, 13, 16, 20, 25, 27, 28, 26, 31, 33, 44, 42, 47, 52, 48, 54, 52, 60, 64, 68, 64, 67, 68, 77, 108, 94, 102, 95, 106, 100, 103, 106, 105, 106, 115, 110, 127, 120, 131, 122, 143, 159, 149, 148, 156, 149, 151, 155, 165, 162, 167, 174, 175 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Gilbreath's triangle is a triangle of numbers arising from Gilbreath's conjecture: successive absolute differences of primes. LINKS FORMULA a(n) = A173816(n)/2. MAPLE A036262 := proc(n, k) option remember ; if k = n then ithprime(n) ; else abs(procname(n, k+1)-procname(n-1, k)) ; end if; end proc: A173818 := proc(n) add(A036262(n, k), k=1..n)/2 ; end proc: seq(A173818(n), n=1..90) ; # R. J. Mathar, Mar 01 2010 CROSSREFS Cf. A036261, A036262, A173816. Sequence in context: A335315 A307805 A189767 * A198383 A334268 A220696 Adjacent sequences:  A173814 A173815 A173816 * A173818 A173819 A173820 KEYWORD nonn AUTHOR Juri-Stepan Gerasimov, Feb 25 2010 EXTENSIONS a(23) and a(24) corrected and sequence extended by R. J. Mathar, Mar 01 2010 STATUS approved

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Last modified September 21 09:06 EDT 2021. Contains 347597 sequences. (Running on oeis4.)