Śatapatha Brāhmaṇa ("of a hundred paths") 10.2.6.2

10.2.6.2

sa ṛtubhireva saptavidhaḥ ṣaḍṛtavaḥ saṃvatsara eva saptamī vidhā tasyaitasya saṃvatsarasyaitattejo ya eṣa tapati tasya raśmayaḥ śataṃ vidhā maṇḍalamevaikaśatatamī vidhā

By the seasons it is sevenfold,--six seasons (of two months), and the year itself as the seventh part. And he who shines yonder is the light of that year: his rays are a hundredfold, and the (sun's) disk itself is the one hundred and first part.