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A193699 Number of arrays of -5..5 integers x(1..n) with every x(i) in a subsequence of length 1, 2 or 3 with sum zero 1
1, 11, 101, 491, 3141, 19301, 115761, 706591, 4292223, 26065517, 158426129, 962553071, 5848496923, 35536745667, 215924096065, 1311980244395, 7971749802937, 48437255764809, 294310402140129, 1788264132674883 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 5 of A193702

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

FORMULA

Empirical: a(n) = 7*a(n-1) -10*a(n-2) +12*a(n-3) +40*a(n-4) +244*a(n-5) +3*a(n-6) +1089*a(n-7) +3707*a(n-8) +6208*a(n-9) +11413*a(n-10) +54122*a(n-11) +73396*a(n-12) +158607*a(n-13) +405718*a(n-14) +701801*a(n-15) +1089821*a(n-16) +2395265*a(n-17) +3200288*a(n-18) +4951404*a(n-19) +6944714*a(n-20) +8209743*a(n-21) +6954175*a(n-22) +5206414*a(n-23) -8778901*a(n-24) -18668023*a(n-25) -42468364*a(n-26) -49526242*a(n-27) -51648621*a(n-28) -18663384*a(n-29) +10565942*a(n-30) +78511699*a(n-31) +71823492*a(n-32) +108577171*a(n-33) +19543205*a(n-34) +19288879*a(n-35) -71137204*a(n-36) -42763958*a(n-37) -65244582*a(n-38) -16175672*a(n-39) -11174774*a(n-40) +13423392*a(n-41) +10575176*a(n-42) +12859223*a(n-43) +6625040*a(n-44) +4102636*a(n-45) +1041074*a(n-46) +129924*a(n-47) -376260*a(n-48) -325965*a(n-49) -242219*a(n-50) -129056*a(n-51) -62894*a(n-52) -25836*a(n-53) -9900*a(n-54) -3275*a(n-55) -954*a(n-56) -243*a(n-57) -55*a(n-58) -10*a(n-59) -a(n-60)

EXAMPLE

Some solutions for n=6

.-4...-3....2...-4....1...-3...-2...-1....4....1....2....4....4....4....0...-5

..4....3...-2....1....4....3....2....1....1...-5...-2...-4....0...-4....2....5

..1....0....4....3...-5...-5....1....0...-5....4...-5...-2...-4....4...-2...-5

.-5....3...-2...-4....3....5....4...-1....5...-1....5....2...-1...-3...-5....4

..2...-5....1....1....2...-5...-5....1....3...-4....0...-4...-2...-2....2...-4

.-2....2...-1....0...-5....0....5....0...-3....5...-5....2....3....5....3....0

CROSSREFS

Sequence in context: A121402 A156307 A057532 * A001603 A113403 A045624

Adjacent sequences:  A193696 A193697 A193698 * A193700 A193701 A193702

KEYWORD

nonn

AUTHOR

R. H. Hardin Aug 02 2011

STATUS

approved

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Last modified December 1 21:42 EST 2020. Contains 338858 sequences. (Running on oeis4.)