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 A334745 Starting with a(1) = a(2) = 1, proceed in a square spiral, computing each term as the sum of diagonally adjacent prior terms. 2
 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 3, 2, 3, 1, 1, 3, 2, 3, 1, 1, 3, 3, 3, 3, 1, 1, 3, 3, 3, 3, 1, 1, 4, 3, 6, 3, 4, 1, 1, 4, 3, 6, 3, 4, 1, 1, 4, 4, 6, 6, 4, 4, 1, 1, 4, 4, 6, 6, 4, 4, 1, 1, 5, 4, 10, 6, 10, 4, 5, 1, 1, 5, 4, 10, 6 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,8 LINKS Peter Kagey, Table of n, a(n) for n = 1..10000 Peter Kagey, Bitmap illustrating the parity of the first 2^22 terms. (Even and odd numbers are represented with black and white pixels respectively.) FORMULA Conjecture: a(2n-1) = A247976(n). EXAMPLE Spiral begins: ... 3---3---3---3---1 | 1---1---2---2---1 1 | | | 2 1---1---1 1 3 | | | | | 2 1 1---1 2 2 | | | | 1 1---2---1---1 3 | | 1---3---2---3---1---1 The last illustrated term above is a(35) = 3 = 2 + 1 because diagonally down-right is 2 and diagonally down-left is 1. CROSSREFS Cf. A141481, A278180, A334741, A334742. The x- and y-coordinates at n-th step are A174344 and A274923 respectively. Sequence in context: A307017 A220424 A182907 * A323231 A175128 A359307 Adjacent sequences: A334742 A334743 A334744 * A334746 A334747 A334748 KEYWORD nonn AUTHOR Alec Jones and Peter Kagey, May 09 2020 STATUS approved

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Last modified December 11 00:22 EST 2023. Contains 367717 sequences. (Running on oeis4.)