N begins at 0; retain sequence order and repeated values. A finite prefix does not determine a unique infinite rule, convergence, or infinite series. L=0; only 0≤n<L is allowed for a_n=1+(2)n. Ordered candidate indices=[-1, 0, 1]. Give (L, index-eligibility mask, legal term values or invalid-index).
G001 — N begins at 0; retain sequence order and repeated values. A finite prefix does not determine a unique infinite rule, convergence, or infinite series. L=0; only 0≤n<L is allowed for a_n=1+(2)n. Ordered candidate indices=[-1, 0, 1]. Give (L, index-eligibility mask, legal term values or invalid-index).
Definition and scope
Use the original question domain, assumptions and cited MKO definitions. This item has second-context mathematical and bilingual review, with the model, answer and every arithmetic step independently recomputed from the original parameters; the source question remains a candidate.
N starts at0;ordered finite indices and repeated values retained
After
given recurrences differ from guessing an infinite rule from observations
Conditions: none
Sequences are ordered and may repeat.A finite observed prefix alone does not determine a unique infinite rule;when a recurrence is explicitly supplied,use that rule rather than inventing one.
Step identifiers and dependencies
Rule: finite_ordered_sequence_scope · Uses: G001
S002 · implies
Before
candidate index=-1;0≤index<0=No
After
value/status=invalid index
Conditions: none
An outside candidate is not an already supplied term,even if a number could be inserted into an extrapolated formula.L=0 has no legal indices.
S004 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
S003 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
S002 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
S001 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
Result
(0, [No, No, No], [invalid-index, invalid-index, invalid-index])
The full substitutions and premise checks give the original answer; source identity,format and status are unchanged.
This question review and source binding
Review date: 2026-10-26
Original questions, answers, step expressions, numeric ASTs and historical records are retained. Source candidate labels remain historical and are not overwritten as formal proof.