The first, 50, terms of the sequence enumerating permutations of length n suc\
    h that |pi[i+5]-pi[i]| is never 5 are





[1, 2, 6, 24, 120, 672, 4128, 28992, 231936, 2088960, 20434944, 221871360, 
2645370624, 34344038400, 482103767040, 7269498483456, 117240911729664, 
2013265377314688, 36665783917283328, 705762463906133760, 14313891805008665856,
305058200866133496192, 6815052066896539474560, 159241382359638761724672, 
3883921082001847040221440, 98699868661535185749114624, 
2608949810397316102581264000, 71622186742768413689449287552, 
2039124039527206695305943379200, 60128636818742572091828821973760, 
1834125525117506833382949381816576, 57808498790020661970656015543954304, 
1880646302176977415309283405157735552, 63087438203981016641562457251807096576,
2180185294898959731419619368810528298240, 
77549229163828853597972920846931232317184, 
2836848811167470025902536150592499417336960, 
106642644947448725710055247245890264495920000, 
4116628209806113469428707515857149702519259392, 
163066790634733919894992999634610664894428629760, 
6623925180895741094555642819931481074970225049856, 
275752050231190603966661231196874829453787350659968, 
11757538084172715269956450158137439255668036134694016, 
513170516348942479904033294814738996628656401048461056, 
22914985443156415514045218373982436375943375502024234240, 
1046322988333048044923089654820852427812577760517749430016, 
48829917574082286636152513872503988724848599908406007616640, 
2327959318184085117777130658054123303305815250037555430705024, 
113328163785756071344174854474263599965779017303294208752689408, 
5630999643418367939475904893793538098552725610904063075064840960]


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